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TDMS Study 05002-06 Pathology Tables


                                     INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)
                                                        GAMMA-BUTYROLACTONE


NTP Experiment-Test: 05002-06                                                                                     Report: PEIRPT03
Study Type: CHRONIC                                                                                               Date: 09/02/94
Route: GAVAGE                                                                                                     Time: 19:42:04




       Facility:  Southern Research Institute

       Chemical CAS #:  96-48-0

       Lock Date:  None

       Cage Range:  All

       Reasons For Removal:    All

       Removal Date Range:     All

       Treatment Groups:       Include All
































a  Number of animals examined microscopically at site and number of animals with lesion

                                                             Page   1

NTP Experiment-Test: 05002-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                        GAMMA-BUTYROLACTONE                                    Date: 09/02/94  
Route: GAVAGE                                                                                                     Time: 19:42:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        VEHICLE      262.         525.                                                   
                                                   CONTROL      MG/KG        MG/KG                                                  
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          50           50           50                                                  
  Early Deaths                                                                                                                      
    Moribund                                           8           11            9                                                  
    Dead                                               4            5            3                                                  
  Survivors                                                                                                                         
    Terminal Sacrifice                                38           34           38                                                  
  Animals Examined Microscopically                    50           50           50                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Gallbladder                                        (47)                      (47)                                                
      Dilatation                                                                 1 (2%)                                             
      Inflammation, Chronic                            3 (6%)                    1 (2%)                                             
   Intestine Large, Cecum                             (48)                      (48)                                                
      Edema                                            2 (4%)                                                                       
      Hyperplasia, Lymphoid                            1 (2%)                                                                       
   Intestine Small, Ileum                             (48)         (1)          (49)                                                
      Hyperplasia, Lymphoid                            1 (2%)       1 (100%)     2 (4%)                                             
   Intestine Small, Jejunum                           (49)                      (49)                                                
      Hyperplasia, Lymphoid                                                      1 (2%)                                             
   Liver                                              (50)         (50)         (50)                                                
      Basophilic Focus                                                           1 (2%)                                             
      Cyst                                                          1 (2%)                                                          
      Eosinophilic Focus                               1 (2%)                                                                       
      Focal Cellular Change                                                      1 (2%)                                             
      Hematopoietic Cell Proliferation                              2 (4%)       2 (4%)                                             
      Inflammation, Chronic                           14 (28%)      7 (14%)      6 (12%)                                            
      Mineralization                                   1 (2%)                    1 (2%)                                             
      Hepatocyte, Vacuolization Cytoplasmic            8 (16%)      2 (4%)       2 (4%)                                             
      Kupffer Cell, Hyperplasia                        1 (2%)       8 (16%)      3 (6%)                                             
      Kupffer Cell, Pigmentation                       1 (2%)                                                                       
      Lobules, Necrosis                                1 (2%)       3 (6%)       3 (6%)                                             
   Mesentery                                          (3)          (5)          (5)                                                 
      Accessory Spleen                                 1 (33%)                                                                      
      Cyst                                                                       1 (20%)                                            
      Inflammation, Suppurative                                     1 (20%)      1 (20%)                                            
      Fat, Inflammation, Granulomatous                 1 (33%)                                                                      
      Fat, Necrosis                                    2 (67%)      1 (20%)      1 (20%)                                            
   Pancreas                                           (50)         (50)         (48)                                                
      Atrophy                                                       1 (2%)       4 (8%)                                             
      Cyst                                             1 (2%)                    1 (2%)                                             
      Hyperplasia, Nodular                                                       1 (2%)                                             
      Inflammation, Chronic                            7 (14%)      3 (6%)       5 (10%)                                            
      Necrosis                                         2 (4%)                                                                       
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    2                                                              
NTP Experiment-Test: 05002-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                        GAMMA-BUTYROLACTONE                                    Date: 09/02/94  
Route: GAVAGE                                                                                                     Time: 19:42:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        VEHICLE      262.         525.                                                   
                                                   CONTROL      MG/KG        MG/KG                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Pigmentation                                     2 (4%)                                                                       
   Salivary Glands                                    (50)                      (50)                                                
      Hyperplasia, Lymphoid                                                      1 (2%)                                             
      Inflammation, Chronic                            7 (14%)                  10 (20%)                                            
   Stomach, Forestomach                               (50)         (49)         (50)                                                
      Diverticulum                                     1 (2%)       1 (2%)       4 (8%)                                             
      Inflammation, Chronic                                         1 (2%)                                                          
      Mucosa, Dysplasia                                                          1 (2%)                                             
      Mucosa, Hyperplasia                             10 (20%)      2 (4%)       7 (14%)                                            
   Stomach, Glandular                                 (50)         (50)         (50)                                                
      Cyst                                                          1 (2%)       1 (2%)                                             
      Dysplasia                                                                  1 (2%)                                             
      Erosion                                          1 (2%)                    2 (4%)                                             
      Inflammation, Chronic Active                                  1 (2%)       1 (2%)                                             
      Mineralization                                   2 (4%)                    3 (6%)                                             
      Ulcer                                            1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (50)                      (50)                                                
      Myocardium, Mineralization                                                 2 (4%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Gland, Cortex                              (50)         (1)          (50)                                                
      Accessory Adrenal Cortical Nodule                1 (2%)                    2 (4%)                                             
      Angiectasis                                                   1 (100%)                                                        
      Cyst                                                                       1 (2%)                                             
      Developmental Malformation                                                 2 (4%)                                             
      Inflammation, Chronic                            1 (2%)                                                                       
      Spindle Cell, Hyperplasia                       43 (86%)                  46 (92%)                                            
      Zona Fasciculata, Hyperplasia, Focal             1 (2%)                                                                       
   Adrenal Gland, Medulla                             (50)                      (49)                                                
      Hyperplasia                                      3 (6%)                    1 (2%)                                             
   Islets, Pancreatic                                 (50)         (49)         (47)                                                
      Amyloid Deposition                                            1 (2%)                                                          
      Hyperplasia                                      5 (10%)      4 (8%)       6 (13%)                                            
      Inflammation, Chronic                            1 (2%)                                                                       
   Parathyroid Gland                                  (47)                      (47)                                                
      Cyst                                                                       1 (2%)                                             
   Pituitary Gland                                    (48)         (48)         (43)                                                
      Pars Distalis, Angiectasis                       4 (8%)       5 (10%)      2 (5%)                                             
      Pars Distalis, Cyst                                           1 (2%)       1 (2%)                                             
      Pars Distalis, Hyperplasia                      13 (27%)     12 (25%)      7 (16%)                                            
   Thyroid Gland                                      (49)         (48)         (50)                                                
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    3                                                              
NTP Experiment-Test: 05002-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                        GAMMA-BUTYROLACTONE                                    Date: 09/02/94  
Route: GAVAGE                                                                                                     Time: 19:42:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        VEHICLE      262.         525.                                                   
                                                   CONTROL      MG/KG        MG/KG                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Cyst                                             2 (4%)       9 (19%)      1 (2%)                                             
      Inflammation, Chronic                            3 (6%)       2 (4%)       1 (2%)                                             
      Follicular Cell, Hyperplasia                     5 (10%)      7 (15%)      1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                                               (1)                                                 
      Ectasia                                                                    1 (100%)                                           
      Inflammation, Chronic                                                      1 (100%)                                           
   Ovary                                              (48)         (49)         (46)                                                
      Cyst                                            11 (23%)     14 (29%)     14 (30%)                                            
      Hemorrhage                                       2 (4%)       5 (10%)      1 (2%)                                             
      Inflammation, Chronic                            1 (2%)       1 (2%)                                                          
      Inflammation, Suppurative                                     6 (12%)      1 (2%)                                             
   Uterus                                             (50)         (41)         (50)                                                
      Angiectasis                                                   1 (2%)                                                          
      Exudate                                          8 (16%)     14 (34%)      3 (6%)                                             
      Hemorrhage                                       2 (4%)                                                                       
      Hydrometra                                       9 (18%)      4 (10%)      5 (10%)                                            
      Hyperplasia, Cystic                             46 (92%)     37 (90%)     48 (96%)                                            
      Hyperplasia, Glandular                                        2 (5%)                                                          
      Inflammation, Suppurative                                     1 (2%)       1 (2%)                                             
      Metaplasia, Squamous                             1 (2%)       2 (5%)       2 (4%)                                             
      Serosa, Cyst                                     1 (2%)                                                                       
   Vagina                                             (2)                       (1)                                                 
      Granuloma                                                                  1 (100%)                                           
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Blood                                                           (1)          (1)                                                 
      Anemia                                                        1 (100%)     1 (100%)                                           
      Leukocytosis                                                  1 (100%)     1 (100%)                                           
   Bone Marrow                                        (50)         (50)         (50)                                                
      Myelofibrosis                                   41 (82%)     41 (82%)     42 (84%)                                            
      Necrosis                                                      1 (2%)                                                          
      Proliferation                                    1 (2%)       6 (12%)      2 (4%)                                             
   Lymph Node                                         (50)         (6)          (49)                                                
      Iliac, Angiectasis                                                         1 (2%)                                             
      Iliac, Hyperplasia, Lymphoid                     1 (2%)                                                                       
      Iliac, Hyperplasia, Plasma Cell                                            1 (2%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    4                                                              
NTP Experiment-Test: 05002-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                        GAMMA-BUTYROLACTONE                                    Date: 09/02/94  
Route: GAVAGE                                                                                                     Time: 19:42:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        VEHICLE      262.         525.                                                   
                                                   CONTROL      MG/KG        MG/KG                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Iliac, Infiltration Cellular,                                                                                                 
          Polymorphonuclear                            1 (2%)                                                                       
      Inguinal, Hyperplasia, Lymphoid                                            1 (2%)                                             
      Renal, Hyperplasia, Lymphoid                     1 (2%)                                                                       
      Renal, Hyperplasia, Plasma Cell                               1 (17%)      1 (2%)                                             
   Lymph Node, Mandibular                             (47)         (1)          (45)                                                
      Hyperplasia, Lymphoid                                                      1 (2%)                                             
   Lymph Node, Mesenteric                             (49)         (5)          (43)                                                
      Ectasia                                                       1 (20%)                                                         
      Hemorrhage                                       2 (4%)                    2 (5%)                                             
      Hyperplasia, Reticulum Cell                                   1 (20%)                                                         
   Spleen                                             (50)         (14)         (50)                                                
      Angiectasis                                                                1 (2%)                                             
      Developmental Malformation                       1 (2%)                                                                       
      Hematopoietic Cell Proliferation                 6 (12%)      7 (50%)      8 (16%)                                            
      Hyperplasia, Lymphoid                            3 (6%)       2 (14%)      5 (10%)                                            
      Lymphoid Follicle, Depletion Cellular            2 (4%)                    1 (2%)                                             
      Red Pulp, Depletion Cellular                     2 (4%)                                                                       
      Sinusoid, Hyperplasia                                                      1 (2%)                                             
   Thymus                                             (47)         (2)          (44)                                                
      Cyst                                                                       1 (2%)                                             
      Hyperplasia, Lymphoid                                         1 (50%)      2 (5%)                                             
      Epithelial Cell, Hyperplasia                     1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (50)         (48)         (50)                                                
      Hyperplasia, Cystic                             17 (34%)     19 (40%)     18 (36%)                                            
      Hyperplasia, Lobular                                          2 (4%)       2 (4%)                                             
      Infiltration Cellular, Histiocyte                1 (2%)                                                                       
      Inflammation, Chronic                                         1 (2%)                                                          
   Skin                                               (50)         (47)         (50)                                                
      Acanthosis                                       3 (6%)       1 (2%)       3 (6%)                                             
      Cyst Epithelial Inclusion                                                  1 (2%)                                             
      Fibrosis                                         1 (2%)                    1 (2%)                                             
      Hemorrhage                                                                 1 (2%)                                             
      Inflammation, Chronic                            1 (2%)                    1 (2%)                                             
      Ulcer                                                                      1 (2%)                                             
      Sebaceous Gland, Hyperplasia                                               1 (2%)                                             
      Subcutaneous Tissue, Edema                                    1 (2%)       1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    5                                                              
NTP Experiment-Test: 05002-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                        GAMMA-BUTYROLACTONE                                    Date: 09/02/94  
Route: GAVAGE                                                                                                     Time: 19:42:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        VEHICLE      262.         525.                                                   
                                                   CONTROL      MG/KG        MG/KG                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)                                                
      Coccygeal, Fibrosis                                           1 (2%)                                                          
      Coccygeal, Hyperplasia                                        1 (2%)                                                          
   Skeletal Muscle                                    (1)          (4)                                                              
      Inflammation, Suppurative                                     1 (25%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (50)                                                
      Compression                                      2 (4%)                                                                       
      Hemorrhage                                       1 (2%)                                                                       
      Infiltration Cellular, Histiocyte                1 (2%)       1 (2%)                                                          
      Inflammation, Chronic                            1 (2%)                                                                       
      Mineralization                                  36 (72%)     28 (56%)     31 (62%)                                            
      Necrosis                                         1 (2%)                                                                       
      Pigmentation                                     1 (2%)                                                                       
      Vacuolization Cytoplasmic                        1 (2%)                                                                       
   Spinal Cord                                        (1)                                                                           
      Degeneration                                     1 (100%)                                                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (50)         (50)                                                
      Congestion                                       1 (2%)                    2 (4%)                                             
      Hemorrhage                                       1 (2%)       1 (2%)       3 (6%)                                             
      Infiltration Cellular, Histiocyte                4 (8%)       3 (6%)       2 (4%)                                             
      Inflammation, Chronic                            6 (12%)     10 (20%)      7 (14%)                                            
      Inflammation, Suppurative                                     1 (2%)       1 (2%)                                             
      Mineralization                                   2 (4%)                    1 (2%)                                             
      Thrombosis                                                    2 (4%)                                                          
      Alveolar Epithelium, Hyperplasia                 2 (4%)                                                                       
      Mediastinum, Necrosis                                                      2 (4%)                                             
   Nose                                               (50)                      (50)                                                
      Exudate                                          2 (4%)                    3 (6%)                                             
      Fungus                                                                     1 (2%)                                             
   Trachea                                            (50)                      (50)                                                
      Inflammation, Chronic Active                                               1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    6                                                              
NTP Experiment-Test: 05002-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                        GAMMA-BUTYROLACTONE                                    Date: 09/02/94  
Route: GAVAGE                                                                                                     Time: 19:42:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        VEHICLE      262.         525.                                                   
                                                   CONTROL      MG/KG        MG/KG                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                             (1)          (2)                                                 
      Cataract                                                      1 (100%)     1 (50%)                                            
      Exudate                                                                    1 (50%)                                            
      Cornea, Hyperplasia                                           1 (100%)     1 (50%)                                            
      Cornea, Inflammation, Chronic                                 1 (100%)     2 (100%)                                           
      Cornea, Mineralization                                                     1 (50%)                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)         (50)                                                
      Casts Protein                                    9 (18%)     15 (30%)      2 (4%)                                             
      Cyst                                             2 (4%)       2 (4%)       1 (2%)                                             
      Glomerulosclerosis                                            2 (4%)       1 (2%)                                             
      Infarct                                                       2 (4%)                                                          
      Inflammation, Chronic                           28 (56%)     26 (52%)     24 (48%)                                            
      Metaplasia, Osseous                              3 (6%)       1 (2%)       2 (4%)                                             
      Mineralization                                   1 (2%)       1 (2%)       2 (4%)                                             
      Renal Tubule, Atrophy                            5 (10%)      3 (6%)       5 (10%)                                            
      Renal Tubule, Dilatation                         1 (2%)       1 (2%)                                                          
      Renal Tubule, Necrosis                           2 (4%)       1 (2%)       1 (2%)                                             
      Renal Tubule, Regeneration                       2 (4%)       3 (6%)       7 (14%)                                            
   Urinary Bladder                                    (50)         (1)          (49)                                                
      Inflammation, Chronic                           35 (70%)                  29 (59%)                                            
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    7                                                              
NTP Experiment-Test: 05002-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                        GAMMA-BUTYROLACTONE                                    Date: 09/02/94  
Route: GAVAGE                                                                                                     Time: 19:42:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          VEHICLE      262.         525.                                                   
                                                   CONTROL      MG/KG        MG/KG                                                  
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          50           50           50                                                  
  Early Deaths                                                                                                                      
    Moribund                                          13            8           23                                                  
    Dead                                               2           12           12                                                  
    Accident                                                                     1                                                  
    Natural Death                                                                1                                                  
    Moribund Sacrifice                                                           1                                                  
  Survivors                                                                                                                         
    Terminal Sacrifice                                35           30           12                                                  
  Animals Examined Microscopically                    50           50           50                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Esophagus                                          (46)         (50)         (47)                                                
      Ulcer                                                                      1 (2%)                                             
   Gallbladder                                        (42)         (41)         (43)                                                
      Ectopic Tissue                                                1 (2%)                                                          
      Fibrosis                                         1 (2%)                                                                       
      Inflammation, Chronic                            1 (2%)                                                                       
      Mineralization                                   1 (2%)                                                                       
   Intestine Large, Cecum                             (47)         (42)         (45)                                                
      Edema                                            1 (2%)                    1 (2%)                                             
      Inflammation, Suppurative                        1 (2%)                    1 (2%)                                             
      Mucosa, Hyperplasia                              1 (2%)                                                                       
   Intestine Large, Rectum                            (49)         (49)         (47)                                                
      Inflammation, Suppurative                                                  1 (2%)                                             
   Intestine Small, Duodenum                          (49)         (49)         (46)                                                
      Ulcer                                                         1 (2%)                                                          
   Intestine Small, Ileum                             (46)         (44)         (44)                                                
      Hyperplasia, Lymphoid                            3 (7%)                                                                       
   Intestine Small, Jejunum                           (47)         (45)         (45)                                                
      Hyperplasia, Lymphoid                            1 (2%)                                                                       
      Inflammation, Chronic Active                                               1 (2%)                                             
      Inflammation, Suppurative                        1 (2%)                                                                       
   Liver                                              (50)         (50)         (50)                                                
      Angiectasis                                                                1 (2%)                                             
      Basophilic Focus                                 1 (2%)       1 (2%)                                                          
      Clear Cell Focus                                                           2 (4%)                                             
      Cyst                                                                       2 (4%)                                             
      Ectopic Tissue                                                1 (2%)                                                          
      Hematopoietic Cell Proliferation                 1 (2%)       1 (2%)                                                          
      Inflammation, Chronic                            4 (8%)       1 (2%)                                                          
      Mineralization                                   4 (8%)                                                                       
      Hepatocyte, Anisokaryosis                        1 (2%)                    2 (4%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    8                                                              
NTP Experiment-Test: 05002-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                        GAMMA-BUTYROLACTONE                                    Date: 09/02/94  
Route: GAVAGE                                                                                                     Time: 19:42:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          VEHICLE      262.         525.                                                   
                                                   CONTROL      MG/KG        MG/KG                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Hepatocyte, Atrophy                              1 (2%)                                                                       
      Hepatocyte, Vacuolization Cytoplasmic            1 (2%)       1 (2%)       1 (2%)                                             
      Kupffer Cell, Hyperplasia                        1 (2%)       2 (4%)       1 (2%)                                             
      Kupffer Cell, Pigmentation                       1 (2%)                                                                       
      Lobules, Necrosis                                6 (12%)      6 (12%)      6 (12%)                                            
   Mesentery                                          (3)          (3)          (7)                                                 
      Artery, Hypertrophy                                                        2 (29%)                                            
      Artery, Inflammation, Chronic Active                          2 (67%)      1 (14%)                                            
      Fat, Hemorrhage                                  1 (33%)                                                                      
      Fat, Inflammation, Chronic                                                 1 (14%)                                            
      Fat, Inflammation, Suppurative                                             1 (14%)                                            
      Fat, Mineralization                              1 (33%)                                                                      
      Fat, Necrosis                                    2 (67%)      1 (33%)      2 (29%)                                            
   Pancreas                                           (50)         (49)         (49)                                                
      Amyloid Deposition                                            1 (2%)                                                          
      Atrophy                                          2 (4%)       1 (2%)                                                          
      Cyst                                             1 (2%)                    1 (2%)                                             
      Fibrosis                                                      2 (4%)                                                          
      Necrosis                                                      1 (2%)       1 (2%)                                             
   Salivary Glands                                    (48)         (50)         (48)                                                
      Atrophy                                                                    1 (2%)                                             
      Inflammation, Chronic                            9 (19%)      9 (18%)      2 (4%)                                             
   Stomach, Forestomach                               (50)         (49)         (49)                                                
      Diverticulum                                     2 (4%)       4 (8%)       1 (2%)                                             
      Inflammation, Chronic                                                      1 (2%)                                             
      Mineralization                                   1 (2%)                                                                       
      Mucosa, Hyperplasia                              2 (4%)                    5 (10%)                                            
   Stomach, Glandular                                 (50)         (49)         (49)                                                
      Cyst                                                          1 (2%)       2 (4%)                                             
      Erosion                                                                    1 (2%)                                             
      Inflammation, Chronic                                         1 (2%)                                                          
      Inflammation, Chronic Active                                  1 (2%)       1 (2%)                                             
      Mineralization                                   3 (6%)                    2 (4%)                                             
      Ulcer                                                         1 (2%)                                                          
      Mucosa, Hyperplasia                                           1 (2%)       1 (2%)                                             
   Tongue                                                          (1)          (2)                                                 
      Necrosis                                                                   1 (50%)                                            
   Tooth                                              (10)         (5)          (3)                                                 
      Dysplasia                                        8 (80%)      4 (80%)      3 (100%)                                           
      Inflammation, Chronic                                                      1 (33%)                                            
      Inflammation, Suppurative                        2 (20%)      3 (60%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    9                                                              
NTP Experiment-Test: 05002-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                        GAMMA-BUTYROLACTONE                                    Date: 09/02/94  
Route: GAVAGE                                                                                                     Time: 19:42:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          VEHICLE      262.         525.                                                   
                                                   CONTROL      MG/KG        MG/KG                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (50)         (50)         (50)                                                
      Artery, Hypertrophy                                                        1 (2%)                                             
      Artery, Inflammation, Chronic Active                                       1 (2%)                                             
      Myocardium, Degeneration                                      1 (2%)                                                          
      Myocardium, Fibrosis                                                       1 (2%)                                             
      Myocardium, Inflammation, Chronic                1 (2%)       1 (2%)                                                          
      Myocardium, Karyomegaly                                       2 (4%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Gland, Cortex                              (48)         (50)         (50)                                                
      Accessory Adrenal Cortical Nodule                             1 (2%)       2 (4%)                                             
      Basophilic Focus                                 1 (2%)                                                                       
      Cyst                                                          1 (2%)                                                          
      Developmental Malformation                       1 (2%)       2 (4%)       2 (4%)                                             
      Hyperplasia, Focal                                                         1 (2%)                                             
      Hypertrophy, Focal                               3 (6%)       1 (2%)                                                          
      Vacuolization Cytoplasmic                        1 (2%)                                                                       
      Spindle Cell, Hyperplasia                       18 (38%)     10 (20%)      8 (16%)                                            
   Adrenal Gland, Medulla                             (48)         (50)         (50)                                                
      Cyst                                                                       1 (2%)                                             
      Hyperplasia                                      2 (4%)       9 (18%)      4 (8%)                                             
      Infiltration Cellular, Mononuclear Cell          1 (2%)                                                                       
   Islets, Pancreatic                                 (50)         (49)         (48)                                                
      Hyperplasia                                     14 (28%)      8 (16%)      2 (4%)                                             
   Parathyroid Gland                                  (45)         (48)         (43)                                                
      Cyst                                             1 (2%)       1 (2%)       1 (2%)                                             
   Pituitary Gland                                    (43)         (48)         (43)                                                
      Pars Distalis, Cyst                              3 (7%)       5 (10%)      2 (5%)                                             
      Pars Distalis, Hyperplasia                                                 2 (5%)                                             
   Thyroid Gland                                      (49)         (50)         (48)                                                
      Cyst                                                          5 (10%)      3 (6%)                                             
      Inflammation, Chronic                            1 (2%)                                                                       
      Inflammation, Suppurative                                     1 (2%)       1 (2%)                                             
      Follicular Cell, Hyperplasia                     3 (6%)       1 (2%)       2 (4%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   10                                                              
NTP Experiment-Test: 05002-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                        GAMMA-BUTYROLACTONE                                    Date: 09/02/94  
Route: GAVAGE                                                                                                     Time: 19:42:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          VEHICLE      262.         525.                                                   
                                                   CONTROL      MG/KG        MG/KG                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (50)         (50)         (49)                                                
      Atypia Cellular                                  1 (2%)                                                                       
      Ectasia                                                                    1 (2%)                                             
      Fibrosis                                                                   1 (2%)                                             
      Granuloma Sperm                                                            2 (4%)                                             
      Inflammation, Chronic                                         1 (2%)       1 (2%)                                             
   Penis                                              (1)          (1)          (2)                                                 
      Inflammation, Chronic Active                                               1 (50%)                                            
   Preputial Gland                                    (18)         (20)         (17)                                                
      Atrophy                                                                    1 (6%)                                             
      Ectasia                                          9 (50%)      9 (45%)      7 (41%)                                            
      Inflammation, Chronic                           11 (61%)     16 (80%)     13 (76%)                                            
      Inflammation, Suppurative                        4 (22%)      5 (25%)      6 (35%)                                            
   Prostate                                           (49)         (48)         (48)                                                
      Fibrosis                                                      1 (2%)                                                          
      Inflammation, Chronic                                         1 (2%)                                                          
      Inflammation, Chronic Active                                  1 (2%)                                                          
      Inflammation, Suppurative                        1 (2%)       5 (10%)      8 (17%)                                            
      Epithelium, Hyperplasia                                       1 (2%)                                                          
   Seminal Vesicle                                    (8)          (5)          (9)                                                 
      Dilatation                                                    1 (20%)                                                         
      Fibrosis                                         2 (25%)      2 (40%)      4 (44%)                                            
      Inflammation, Chronic                            2 (25%)                   1 (11%)                                            
      Inflammation, Suppurative                        1 (13%)      2 (40%)                                                         
   Testes                                             (50)         (50)         (50)                                                
      Fibrosis                                         1 (2%)       1 (2%)       1 (2%)                                             
      Granuloma Sperm                                  1 (2%)                                                                       
      Mineralization                                   5 (10%)      9 (18%)      5 (10%)                                            
      Spermatocele                                                  1 (2%)                                                          
      Seminiferous Tubule, Atrophy                     4 (8%)       8 (16%)      4 (8%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Blood                                              (7)          (2)          (1)                                                 
      Anemia                                           1 (14%)      1 (50%)                                                         
   Bone Marrow                                        (50)         (50)         (49)                                                
      Angiectasis                                                   1 (2%)       1 (2%)                                             
      Hyperplasia, Reticulum Cell                                   1 (2%)                                                          
      Myelofibrosis                                                 1 (2%)       2 (4%)                                             
      Necrosis                                         1 (2%)                                                                       
      Proliferation                                    6 (12%)     12 (24%)      8 (16%)                                            
   Lymph Node                                         (50)         (50)         (49)                                                
      Iliac, Hyperplasia, Lymphoid                                  1 (2%)                                                          
      Iliac, Hyperplasia, Plasma Cell                                            2 (4%)                                             
      Inguinal, Hyperplasia, Histiocytic                            4 (8%)                                                          
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   11                                                              
NTP Experiment-Test: 05002-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                        GAMMA-BUTYROLACTONE                                    Date: 09/02/94  
Route: GAVAGE                                                                                                     Time: 19:42:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          VEHICLE      262.         525.                                                   
                                                   CONTROL      MG/KG        MG/KG                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Inguinal, Hyperplasia, Lymphoid                               5 (10%)      5 (10%)                                            
      Inguinal, Hyperplasia, Plasma Cell                            4 (8%)       2 (4%)                                             
      Mediastinal, Hemorrhage                          1 (2%)                                                                       
      Mediastinal, Inflammation, Suppurative           1 (2%)                                                                       
      Renal, Hyperplasia, Lymphoid                                  1 (2%)                                                          
      Renal, Hyperplasia, Plasma Cell                                            1 (2%)                                             
   Lymph Node, Mandibular                             (45)         (46)         (46)                                                
      Depletion Cellular                                                         1 (2%)                                             
      Hyperplasia, Lymphoid                            1 (2%)                                                                       
      Hyperplasia, Plasma Cell                         1 (2%)                                                                       
      Lymphatic, Dilatation                            1 (2%)                                                                       
   Lymph Node, Mesenteric                             (48)         (46)         (41)                                                
      Depletion Cellular                                                         3 (7%)                                             
      Hematopoietic Cell Proliferation                              1 (2%)                                                          
      Hemorrhage                                      11 (23%)      7 (15%)      5 (12%)                                            
      Hyperplasia, Lymphoid                            3 (6%)                    1 (2%)                                             
      Infiltration Cellular, Megakaryocyte             1 (2%)                                                                       
      Necrosis                                         1 (2%)                                                                       
   Spleen                                             (50)         (50)         (48)                                                
      Erythrophagocytosis                                           1 (2%)                                                          
      Hematopoietic Cell Proliferation                14 (28%)     12 (24%)     18 (38%)                                            
      Hyperplasia, Lymphoid                            5 (10%)                   2 (4%)                                             
      Hyperplasia, Re Cell                                          1 (2%)                                                          
      Pigmentation, Hemosiderin                                     1 (2%)                                                          
      Lymphoid Follicle, Depletion Cellular            2 (4%)       3 (6%)       8 (17%)                                            
      Red Pulp, Depletion Cellular                     1 (2%)       1 (2%)                                                          
   Thymus                                             (42)         (39)         (38)                                                
      Cyst                                             2 (5%)       2 (5%)       1 (3%)                                             
      Depletion Cellular                                            5 (13%)      6 (16%)                                            
      Epithelial Cell, Hyperplasia                                  4 (10%)      4 (11%)                                            
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Skin                                               (50)         (50)         (50)                                                
      Acanthosis                                      12 (24%)     36 (72%)     39 (78%)                                            
      Cyst Epithelial Inclusion                                                  1 (2%)                                             
      Dysplasia                                                                  1 (2%)                                             
      Exudate                                          1 (2%)       4 (8%)       5 (10%)                                            
      Fibrosis                                         1 (2%)       3 (6%)                                                          
      Hemorrhage                                                    2 (4%)                                                          
      Hyperkeratosis                                                             1 (2%)                                             
      Hyperplasia, Pseudoepitheliomatous                            2 (4%)       2 (4%)                                             
      Inflammation, Chronic                            4 (8%)      17 (34%)     19 (38%)                                            
      Inflammation, Chronic Active                                  1 (2%)                                                          
      Inflammation, Suppurative                        1 (2%)                                                                       
      Mineralization                                   2 (4%)                                                                       
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   12                                                              
NTP Experiment-Test: 05002-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                        GAMMA-BUTYROLACTONE                                    Date: 09/02/94  
Route: GAVAGE                                                                                                     Time: 19:42:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          VEHICLE      262.         525.                                                   
                                                   CONTROL      MG/KG        MG/KG                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
INTEGUMENTARY SYSTEM - CONT                                                                                                         
      Pigmentation                                     3 (6%)      12 (24%)     19 (38%)                                            
      Ulcer                                            4 (8%)      15 (30%)     17 (34%)                                            
      Hair Follicle, Atrophy                           1 (2%)      11 (22%)     16 (32%)                                            
      Lymphatic, Dilatation                                         1 (2%)                                                          
      Subcutaneous Tissue, Edema                       3 (6%)       2 (4%)       2 (4%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)                                                
      Hyperostosis                                     1 (2%)       1 (2%)       2 (4%)                                             
      Inflammation, Chronic                                                      1 (2%)                                             
      Coccygeal, Hyperplasia                                        6 (12%)      1 (2%)                                             
      Coccygeal, Inflammation, Chronic                              3 (6%)       1 (2%)                                             
      Coccygeal, Inflammation, Suppurative                          2 (4%)                                                          
      Tarsal, Hyperplasia                                           1 (2%)       8 (16%)                                            
      Tarsal, Inflammation, Chronic                                              3 (6%)                                             
      Tarsal, Inflammation, Suppurative                             1 (2%)                                                          
   Skeletal Muscle                                    (1)          (4)          (2)                                                 
      Fibrosis                                                                   1 (50%)                                            
      Inflammation, Chronic                                         1 (25%)                                                         
      Necrosis                                                      2 (50%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (49)                                                
      Congestion                                                                 3 (6%)                                             
      Cyst                                             1 (2%)                                                                       
      Mineralization                                  27 (54%)     25 (50%)     24 (49%)                                            
      Necrosis                                         1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (50)         (50)                                                
      Congestion                                       1 (2%)       1 (2%)       4 (8%)                                             
      Hemorrhage                                                    1 (2%)       7 (14%)                                            
      Infiltration Cellular, Histiocyte                3 (6%)       2 (4%)       1 (2%)                                             
      Inflammation, Chronic                            4 (8%)                                                                       
      Inflammation, Suppurative                                     1 (2%)                                                          
      Leukocytosis                                     1 (2%)       2 (4%)       5 (10%)                                            
      Thrombosis                                                    1 (2%)                                                          
      Alveolar Epithelium, Hyperplasia                 1 (2%)       2 (4%)                                                          
      Perivascular, Edema                                           2 (4%)                                                          
   Nose                                               (50)         (50)         (49)                                                
      Exudate                                          4 (8%)                    4 (8%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   13                                                              
NTP Experiment-Test: 05002-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                        GAMMA-BUTYROLACTONE                                    Date: 09/02/94  
Route: GAVAGE                                                                                                     Time: 19:42:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          VEHICLE      262.         525.                                                   
                                                   CONTROL      MG/KG        MG/KG                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
RESPIRATORY SYSTEM - CONT                                                                                                           
      Foreign Body                                     1 (2%)       1 (2%)                                                          
      Inflammation, Chronic                                         1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (3)                       (1)                                                 
      Cataract                                         1 (33%)                                                                      
      Cornea, Hyperplasia                              1 (33%)                                                                      
      Cornea, Inflammation, Chronic                    1 (33%)                                                                      
      Cornea, Inflammation, Granulomatous              1 (33%)                                                                      
   Harderian Gland                                    (9)          (48)                                                             
      Inflammation, Chronic                                         1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)         (50)                                                
      Amyloid Deposition                                            1 (2%)                                                          
      Bacterium                                                                  1 (2%)                                             
      Casts Protein                                    4 (8%)       3 (6%)       2 (4%)                                             
      Cyst                                             4 (8%)      10 (20%)      7 (14%)                                            
      Glomerulosclerosis                                            1 (2%)                                                          
      Hemorrhage                                       1 (2%)                    1 (2%)                                             
      Hydronephrosis                                   2 (4%)                    2 (4%)                                             
      Infarct                                                       2 (4%)                                                          
      Inflammation, Chronic                           21 (42%)     14 (28%)      5 (10%)                                            
      Inflammation, Suppurative                        1 (2%)       3 (6%)       2 (4%)                                             
      Metaplasia, Osseous                              1 (2%)       2 (4%)                                                          
      Mineralization                                   3 (6%)       5 (10%)      4 (8%)                                             
      Glomerulus, Hyperplasia                                       1 (2%)                                                          
      Glomerulus, Necrosis                             1 (2%)                                                                       
      Renal Tubule, Atrophy                            3 (6%)       5 (10%)      8 (16%)                                            
      Renal Tubule, Dilatation                                      2 (4%)       3 (6%)                                             
      Renal Tubule, Dysplasia                                                    1 (2%)                                             
      Renal Tubule, Necrosis                           1 (2%)       1 (2%)       1 (2%)                                             
      Renal Tubule, Regeneration                      25 (50%)     26 (52%)     24 (48%)                                            
      Renal Tubule, Vacuolization Cytoplasmic                                    2 (4%)                                             
   Urethra                                            (1)          (4)          (3)                                                 
      Concretion                                                    1 (25%)                                                         
      Hemorrhage                                       1 (100%)                                                                     
      Inflammation, Suppurative                                     3 (75%)      3 (100%)                                           
      Necrosis                                                      1 (25%)                                                         
      Bulbourethral Gland, Hyperplasia                              1 (25%)                                                         
      Mucosa, Hyperplasia                                           1 (25%)      1 (33%)                                            
   Urinary Bladder                                    (50)         (48)         (48)                                                
      Congestion                                                                 1 (2%)                                             
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   14                                                              
NTP Experiment-Test: 05002-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                        GAMMA-BUTYROLACTONE                                    Date: 09/02/94  
Route: GAVAGE                                                                                                     Time: 19:42:04  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          VEHICLE      262.         525.                                                   
                                                   CONTROL      MG/KG        MG/KG                                                  
____________________________________________________________________________________________________________________________________
                                                                                                                                    
URINARY SYSTEM - CONT                                                                                                               
      Edema                                                                      1 (2%)                                             
      Inflammation, Chronic                            2 (4%)       3 (6%)                                                          
      Inflammation, Chronic Active                                               1 (2%)                                             
      Inflammation, Suppurative                                     1 (2%)       1 (2%)                                             
      Mucosa, Hyperplasia                              2 (4%)       1 (2%)       3 (6%)                                             
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   15                                                              
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                             ----------              END OF REPORT             ----------                                           
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