National Toxicology Program

National Toxicology Program
https://ntp.niehs.nih.gov/go/5823

TDMS Study 89006-06 Pathology Tables

NTP Experiment-Test: 89006-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                                AZT                                            Date: 05/31/96
Route: GAVAGE                                                                                                     Time: 12:30:48

                                                        TWO-YEAR CHRONIC




       Facility:  Southern Research Institute

       Chemical CAS #:  30516-87-1

       Lock Date:  06/04/93

       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: 89006-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                                AZT                                            Date: 05/31/96  
Route: GAVAGE                                                                                                     Time: 12:30:48  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        VEHICLE      30 MG/KG     60 MG/KG     120                                       
                                                   CONTROL                                MG/KG                                     
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Moribund Sacrifice                                 5            5            9            7                                     
    Natural Death                                     11            6            7           11                                     
    Dosing Accident                                                              2            1                                     
    Accidently Killed                                                            1                                                  
  Survivors                                                                                                                         
    Terminal Sacrifice                                34           38           31           31                                     
    Natural Death                                                   1                                                               
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Esophagus                                          (50)         (49)         (50)         (50)                                   
      Necrosis                                                                                1 (2%)                                
      Muscularis, Inflammation, Chronic                                          1 (2%)       1 (2%)                                
   Intestine Large, Colon                             (46)         (48)         (46)         (45)                                   
      Inflammation, Chronic                                                      1 (2%)                                             
   Intestine Large, Cecum                             (46)         (47)         (46)         (45)                                   
      Hemorrhage                                                                              1 (2%)                                
      Inflammation, Chronic                                                                   1 (2%)                                
   Intestine Small, Duodenum                          (46)         (45)         (46)         (44)                                   
      Erosion                                                                    1 (2%)                                             
   Intestine Small, Jejunum                           (46)         (46)         (44)         (42)                                   
      Peyer's Patch, Hyperplasia, Lymphoid                          1 (2%)                                                          
   Intestine Small, Ileum                             (46)         (44)         (45)         (42)                                   
      Peyer's Patch, Hyperplasia, Lymphoid             1 (2%)                                                                       
   Liver                                              (50)         (50)         (50)         (50)                                   
      Angiectasis                                                   1 (2%)                                                          
      Basophilic Focus                                              1 (2%)                    3 (6%)                                
      Clear Cell Focus                                 1 (2%)       3 (6%)       1 (2%)                                             
      Eosinophilic Focus                               6 (12%)     16 (32%)      7 (14%)      7 (14%)                               
      Fibrosis, Focal                                                                         1 (2%)                                
      Hematopoietic Cell Proliferation                              1 (2%)       1 (2%)       1 (2%)                                
      Hepatodiaphragmatic Nodule                       1 (2%)                                                                       
      Inflammation, Chronic                            1 (2%)       2 (4%)       2 (4%)       1 (2%)                                
      Mixed Cell Focus                                 1 (2%)       1 (2%)       5 (10%)                                            
      Necrosis, Focal                                  3 (6%)       3 (6%)       2 (4%)      10 (20%)                               
      Vacuolization Cytoplasmic                        3 (6%)       4 (8%)       3 (6%)       3 (6%)                                
      Hepatocyte, Karyomegaly                          1 (2%)       1 (2%)                                                          
   Mesentery                                          (13)         (17)         (8)          (11)                                   
      Inflammation, Chronic                            1 (8%)                                 1 (9%)                                
      Fat, Necrosis                                    8 (62%)     16 (94%)      5 (63%)     10 (91%)                               
   Pancreas                                           (50)         (49)         (49)         (48)                                   
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    2                                                              
NTP Experiment-Test: 89006-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                                AZT                                            Date: 05/31/96  
Route: GAVAGE                                                                                                     Time: 12:30:48  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        VEHICLE      30 MG/KG     60 MG/KG     120                                       
                                                   CONTROL                                MG/KG                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Atrophy                                          1 (2%)       1 (2%)       2 (4%)       1 (2%)                                
      Atrophy, Diffuse                                 1 (2%)                                                                       
      Inflammation, Chronic                                         2 (4%)                                                          
      Necrosis                                         1 (2%)                                                                       
      Duct, Cyst                                       2 (4%)       1 (2%)       1 (2%)       1 (2%)                                
   Stomach, Forestomach                               (49)         (49)         (49)         (49)                                   
      Cyst                                                          1 (2%)                                                          
      Erosion                                                                    1 (2%)                                             
      Hemorrhage                                                                 1 (2%)                                             
      Inflammation, Chronic                                         1 (2%)       2 (4%)                                             
      Ulcer                                                         1 (2%)       1 (2%)                                             
      Epithelium, Hyperplasia                          4 (8%)       9 (18%)      7 (14%)      3 (6%)                                
   Stomach, Glandular                                 (49)         (49)         (48)         (49)                                   
      Erosion                                          1 (2%)       2 (4%)       1 (2%)       1 (2%)                                
      Mineralization                                   1 (2%)                                 1 (2%)                                
      Necrosis                                                      1 (2%)                                                          
      Glands, Degeneration, Cystic, Focal              1 (2%)       1 (2%)       4 (8%)       4 (8%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Heart                                              (49)         (50)         (50)         (50)                                   
      Inflammation, Chronic, Focal                     1 (2%)       4 (8%)       3 (6%)       3 (6%)                                
      Mineralization                                                1 (2%)       1 (2%)                                             
      Thrombosis                                                                              1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (49)         (50)         (50)                                   
      Accessory Adrenal Cortical Nodule                                          1 (2%)                                             
      Cyst                                                                       1 (2%)                                             
      Cytoplasmic Alteration, Focal                                 4 (8%)       4 (8%)       2 (4%)                                
      Hematopoietic Cell Proliferation                                                        1 (2%)                                
      Hyperplasia, Focal                               1 (2%)                                 1 (2%)                                
      Hypertrophy, Focal                                            2 (4%)       1 (2%)       4 (8%)                                
   Islets, Pancreatic                                 (49)         (49)         (50)         (47)                                   
      Hyperplasia                                                                             2 (4%)                                
   Parathyroid Gland                                  (47)         (45)         (48)         (50)                                   
      Cyst                                                                       1 (2%)       1 (2%)                                
   Pituitary Gland                                    (46)         (49)         (46)         (46)                                   
      Angiectasis                                      1 (2%)       2 (4%)                    1 (2%)                                
      Pars Distalis, Cyst                                           1 (2%)                                                          
      Pars Distalis, Cytoplasmic Alteration, Focal     7 (15%)                   1 (2%)       3 (7%)                                
      Pars Distalis, Hyperplasia, Focal                4 (9%)       7 (14%)      6 (13%)      5 (11%)                               
      Pars Intermedia, Hyperplasia, Focal                                                     2 (4%)                                
   Thyroid Gland                                      (49)         (50)         (50)         (50)                                   
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    3                                                              
NTP Experiment-Test: 89006-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                                AZT                                            Date: 05/31/96  
Route: GAVAGE                                                                                                     Time: 12:30:48  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        VEHICLE      30 MG/KG     60 MG/KG     120                                       
                                                   CONTROL                                MG/KG                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Degeneration, Cystic, Focal                     25 (51%)     19 (38%)     23 (46%)     20 (40%)                               
      Follicle, Cyst                                   2 (4%)       6 (12%)      2 (4%)       7 (14%)                               
      Follicular Cell, Hyperplasia                     6 (12%)     11 (22%)      5 (10%)     11 (22%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Clitoral Gland                                     (49)         (49)         (49)         (48)                                   
      Degeneration, Cystic                            35 (71%)     46 (94%)     33 (67%)     43 (90%)                               
      Inflammation, Chronic                                         1 (2%)       1 (2%)                                             
   Ovary                                              (50)         (50)         (47)         (48)                                   
      Angiectasis                                      1 (2%)                                                                       
      Cyst                                            10 (20%)     10 (20%)      5 (11%)     10 (21%)                               
      Hemorrhage                                       3 (6%)       1 (2%)                    1 (2%)                                
      Hyperplasia, Tubular                                                       1 (2%)                                             
      Thrombosis                                                                 1 (2%)       1 (2%)                                
      Bilateral, Cyst                                                                         1 (2%)                                
   Uterus                                             (50)         (50)         (49)         (50)                                   
      Cyst                                             3 (6%)                                                                       
      Hemorrhage                                       1 (2%)       2 (4%)       2 (4%)       1 (2%)                                
      Hydrometra                                      11 (22%)     20 (40%)     22 (45%)     13 (26%)                               
      Inflammation, Suppurative                        1 (2%)       1 (2%)       1 (2%)       1 (2%)                                
      Thrombosis                                                    1 (2%)       2 (4%)                                             
      Endometrium, Hyperplasia, Cystic                45 (90%)     45 (90%)     36 (73%)     42 (84%)                               
   Vagina                                             (50)         (49)         (45)         (49)                                   
      Cyst                                                                       1 (2%)                                             
      Fibrosis                                                                                1 (2%)                                
      Inflammation, Suppurative                                                               1 (2%)                                
      Epithelium, Hyperplasia                                       3 (6%)       2 (4%)       7 (14%)                               
      Epithelium, Hyperplasia, Atypical                                          2 (4%)       4 (8%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)         (49)         (50)         (50)                                   
      Angiectasis                                                                1 (2%)       1 (2%)                                
      Hyperplasia                                      1 (2%)       3 (6%)       3 (6%)       7 (14%)                               
      Necrosis                                         1 (2%)                                                                       
   Lymph Node                                         (7)          (5)          (7)          (10)                                   
      Bronchial, Hyperplasia                           1 (14%)                                                                      
      Iliac, Ectasia                                                                          1 (10%)                               
      Iliac, Hematopoietic Cell Proliferation                                    1 (14%)                                            
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    4                                                              
NTP Experiment-Test: 89006-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                                AZT                                            Date: 05/31/96  
Route: GAVAGE                                                                                                     Time: 12:30:48  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        VEHICLE      30 MG/KG     60 MG/KG     120                                       
                                                   CONTROL                                MG/KG                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
      Iliac, Hemorrhage                                             1 (20%)                                                         
      Iliac, Hyperplasia, Histiocytic                  1 (14%)                                                                      
      Inguinal, Hyperplasia, Histiocytic                                                      1 (10%)                               
      Inguinal, Hyperplasia, Lymphoid                               1 (20%)      1 (14%)      2 (20%)                               
      Mediastinal, Hemorrhage                          1 (14%)      1 (20%)                                                         
      Mediastinal, Hyperplasia, Histiocytic                                                   1 (10%)                               
      Mediastinal, Hyperplasia, Lymphoid                                                      1 (10%)                               
      Renal, Hyperplasia, Lymphoid                                                            1 (10%)                               
   Lymph Node, Mandibular                             (50)         (46)         (48)         (48)                                   
      Hemorrhage                                                    1 (2%)       1 (2%)                                             
      Hyperplasia, Lymphoid                                         2 (4%)       3 (6%)       6 (13%)                               
      Infiltration Cellular, Mast Cell                 1 (2%)                    1 (2%)                                             
   Lymph Node, Mesenteric                             (50)         (47)         (48)         (47)                                   
      Ectasia                                                       1 (2%)       2 (4%)                                             
      Hematopoietic Cell Proliferation                                           1 (2%)                                             
      Hemorrhage                                       3 (6%)       5 (11%)      2 (4%)       5 (11%)                               
      Hyperplasia, Lymphoid                                         5 (11%)      3 (6%)       5 (11%)                               
   Spleen                                             (49)         (48)         (49)         (50)                                   
      Congestion                                       1 (2%)                    2 (4%)                                             
      Depletion Cellular                                            1 (2%)       3 (6%)       1 (2%)                                
      Hematopoietic Cell Proliferation                13 (27%)     12 (25%)     10 (20%)     14 (28%)                               
      Hyperplasia, Lymphoid                            8 (16%)      6 (13%)      2 (4%)       6 (12%)                               
   Thymus                                             (48)         (46)         (49)         (46)                                   
      Angiectasis                                                   1 (2%)                                                          
      Cyst                                                                       3 (6%)       1 (2%)                                
      Hyperplasia, Lymphoid                            4 (8%)       1 (2%)       1 (2%)       4 (9%)                                
      Necrosis                                                                   2 (4%)       2 (4%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (47)         (47)         (48)         (47)                                   
      Hyperplasia                                                   3 (6%)                    1 (2%)                                
   Skin                                               (50)         (49)         (50)         (50)                                   
      Inflammation, Chronic, Focal                     1 (2%)                    1 (2%)                                             
      Subcutaneous Tissue, Cyst Epithelial                                                                                          
          Inclusion                                                              1 (2%)                                             
      Subcutaneous Tissue, Edema                       1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (50)                                   
      Fibrous Osteodystrophy                                        4 (8%)                                                          
      Hyperostosis                                    37 (74%)     35 (70%)     33 (66%)     37 (74%)                               
      Cranium, Fibrous Osteodystrophy                                                         1 (2%)                                
   Skeletal Muscle                                    (50)         (50)         (50)         (50)                                   
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    5                                                              
NTP Experiment-Test: 89006-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                                AZT                                            Date: 05/31/96  
Route: GAVAGE                                                                                                     Time: 12:30:48  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        VEHICLE      30 MG/KG     60 MG/KG     120                                       
                                                   CONTROL                                MG/KG                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
MUSCULOSKELETAL SYSTEM - CONT                                                                                                       
      Hyperplasia, Focal, Lymphoid                                               1 (2%)                                             
      Inflammation, Suppurative                        1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (50)         (50)                                   
      Atrophy, Focal                                   1 (2%)       3 (6%)                                                          
      Hemorrhage                                       1 (2%)                                                                       
      Vacuolization Cytoplasmic                        1 (2%)                    1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (49)         (50)         (50)         (50)                                   
      Congestion                                                    2 (4%)                    1 (2%)                                
      Foreign Body                                                               1 (2%)       1 (2%)                                
      Hemorrhage                                       3 (6%)                    3 (6%)       1 (2%)                                
      Hyperplasia, Histiocytic                                      2 (4%)       1 (2%)       2 (4%)                                
      Infiltration Cellular, Mixed Cell                1 (2%)                                                                       
      Pigmentation                                                               1 (2%)       1 (2%)                                
      Alveolar Epithelium, Hyperplasia                 2 (4%)                    4 (8%)       1 (2%)                                
      Mediastinum, Hemorrhage                                                    1 (2%)       1 (2%)                                
      Mediastinum, Inflammation, Chronic                                         2 (4%)       1 (2%)                                
      Mediastinum, Necrosis                                                      1 (2%)                                             
   Nose                                               (50)         (50)         (50)         (50)                                   
      Hemorrhage                                       1 (2%)                                                                       
      Mucosa, Glands, Dilatation, Focal                1 (2%)       2 (4%)                    2 (4%)                                
      Nasolacrimal Duct, Cyst                                       1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                (3)                                    (1)                                    
      Cataract                                         1 (33%)                                                                      
      Fibrosis                                         2 (67%)                                                                      
      Cornea, Inflammation, Chronic                                                           1 (100%)                              
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (50)         (50)         (50)                                   
      Cyst                                                                                    1 (2%)                                
      Fibrosis, Focal                                                                         1 (2%)                                
      Infarct                                                       1 (2%)       2 (4%)                                             
      Metaplasia, Focal, Osseous                       1 (2%)                    2 (4%)                                             
      Nephropathy                                     29 (58%)     30 (60%)     31 (62%)     35 (70%)                               
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    6                                                              
NTP Experiment-Test: 89006-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                                AZT                                            Date: 05/31/96  
Route: GAVAGE                                                                                                     Time: 12:30:48  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE FEMALE                        VEHICLE      30 MG/KG     60 MG/KG     120                                       
                                                   CONTROL                                MG/KG                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
URINARY SYSTEM - CONT                                                                                                               
      Pelvis, Dilatation                                                         3 (6%)       3 (6%)                                
      Renal Tubule, Accumulation, Hyaline Droplet                   1 (2%)                    1 (2%)                                
      Renal Tubule, Dilatation                         1 (2%)       1 (2%)       3 (6%)                                             
      Renal Tubule, Necrosis                           1 (2%)                                                                       
      Renal Tubule, Pigmentation                       2 (4%)       1 (2%)                    2 (4%)                                
      Transitional Epithelium, Hyperplasia             1 (2%)                                                                       
   Urinary Bladder                                    (50)         (50)         (49)         (49)                                   
      Hyperplasia, Lymphoid                            1 (2%)       1 (2%)                                                          
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    7                                                              
NTP Experiment-Test: 89006-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                                AZT                                            Date: 05/31/96  
Route: GAVAGE                                                                                                     Time: 12:30:48  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          VEHICLE      30 MG/KG     60 MG/KG     120                                       
                                                   CONTROL                                MG/KG                                     
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY                                                                                                                 
  Animals Initially In Study                          50           50           50           50                                     
  Early Deaths                                                                                                                      
    Natural Death                                     12            6            9            4                                     
    Moribund Sacrifice                                 6            9            9            4                                     
    Accidently Killed                                                            2                                                  
    Dosing Accident                                                              1                                                  
  Survivors                                                                                                                         
    Terminal Sacrifice                                32           35           29           42                                     
  Animals Examined Microscopically                    50           50           50           50                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ALIMENTARY SYSTEM                                                                                                                  
                                                                                                                                    
   Esophagus                                          (50)         (50)         (49)         (50)                                   
      Necrosis                                                                   1 (2%)                                             
      Muscularis, Inflammation, Chronic                                          1 (2%)                                             
   Gallbladder                                        (41)         (42)         (46)         (44)                                   
      Cyst                                                          1 (2%)                                                          
   Intestine Large, Cecum                             (47)         (48)         (45)         (49)                                   
      Hyperplasia, Lymphoid                                                      1 (2%)                                             
   Intestine Small, Duodenum                          (48)         (48)         (47)         (47)                                   
      Cyst                                                                       1 (2%)                                             
      Inflammation, Chronic, Focal                                                            1 (2%)                                
   Intestine Small, Jejunum                           (47)         (48)         (45)         (47)                                   
      Hyperplasia, Adenomatous                         1 (2%)                                                                       
   Intestine Small, Ileum                             (47)         (48)         (45)         (47)                                   
      Peyer's Patch, Hyperplasia, Lymphoid                          1 (2%)       1 (2%)                                             
   Liver                                              (50)         (50)         (50)         (50)                                   
      Angiectasis                                      3 (6%)       1 (2%)                                                          
      Basophilic Focus                                 5 (10%)      1 (2%)       3 (6%)       3 (6%)                                
      Clear Cell Focus                                 4 (8%)       3 (6%)                    4 (8%)                                
      Eosinophilic Focus                              12 (24%)     12 (24%)      7 (14%)     12 (24%)                               
      Inflammation, Chronic                           17 (34%)     24 (48%)     24 (48%)     16 (32%)                               
      Mixed Cell Focus                                 2 (4%)       4 (8%)       7 (14%)      4 (8%)                                
      Necrosis, Focal                                  8 (16%)      8 (16%)      9 (18%)      3 (6%)                                
      Vacuolization Cytoplasmic                        3 (6%)       1 (2%)       4 (8%)       3 (6%)                                
      Bile Duct, Cyst                                  1 (2%)                                 1 (2%)                                
      Bile Duct, Hyperplasia                           1 (2%)       9 (18%)      4 (8%)       3 (6%)                                
      Hepatocyte, Karyomegaly                          7 (14%)     10 (20%)     15 (30%)      5 (10%)                               
   Mesentery                                          (1)          (4)          (5)          (2)                                    
      Hemorrhage                                                                 1 (20%)                                            
      Inflammation, Chronic                                                      1 (20%)                                            
      Inflammation, Granulomatous                      1 (100%)                                                                     
      Thrombosis                                                    1 (25%)                                                         
      Artery, Inflammation, Chronic                                 1 (25%)                                                         
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    8                                                              
NTP Experiment-Test: 89006-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                                AZT                                            Date: 05/31/96  
Route: GAVAGE                                                                                                     Time: 12:30:48  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          VEHICLE      30 MG/KG     60 MG/KG     120                                       
                                                   CONTROL                                MG/KG                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ALIMENTARY SYSTEM - CONT                                                                                                            
      Fat, Necrosis                                                 2 (50%)      2 (40%)      2 (100%)                              
   Pancreas                                           (50)         (49)         (49)         (50)                                   
      Atrophy                                          1 (2%)       3 (6%)       3 (6%)                                             
      Inflammation, Granulomatous                      1 (2%)                                                                       
      Necrosis                                                      1 (2%)                                                          
      Thrombosis                                                                 1 (2%)                                             
      Artery, Inflammation, Chronic                                 1 (2%)                                                          
      Duct, Cyst                                                    1 (2%)       1 (2%)                                             
   Stomach, Forestomach                               (50)         (48)         (49)         (50)                                   
      Erosion                                          1 (2%)                    1 (2%)       1 (2%)                                
      Inflammation, Chronic                            2 (4%)       1 (2%)                                                          
      Ulcer                                            2 (4%)                                 1 (2%)                                
      Epithelium, Hyperplasia                          7 (14%)      4 (8%)       3 (6%)       1 (2%)                                
   Stomach, Glandular                                 (50)         (48)         (49)         (50)                                   
      Erosion                                                       1 (2%)       4 (8%)                                             
      Mineralization                                   1 (2%)       1 (2%)       2 (4%)       2 (4%)                                
      Pigmentation, Focal                                                        1 (2%)                                             
      Glands, Degeneration, Cystic, Focal                           2 (4%)       1 (2%)       2 (4%)                                
   Tooth                                              (2)          (2)          (7)          (1)                                    
      Developmental Malformation                       2 (100%)     2 (100%)     7 (100%)     1 (100%)                              
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 CARDIOVASCULAR SYSTEM                                                                                                              
                                                                                                                                    
   Blood Vessel                                       (50)         (48)         (50)         (50)                                   
      Inflammation, Chronic                            1 (2%)                                 2 (4%)                                
   Heart                                              (50)         (50)         (50)         (50)                                   
      Fibrosis                                         1 (2%)                                                                       
      Inflammation, Chronic, Focal                     2 (4%)       4 (8%)                    1 (2%)                                
      Mineralization                                                             1 (2%)                                             
      Thrombosis                                                    1 (2%)       2 (4%)       1 (2%)                                
      Artery, Inflammation, Chronic                    1 (2%)                                                                       
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 ENDOCRINE SYSTEM                                                                                                                   
                                                                                                                                    
   Adrenal Cortex                                     (50)         (49)         (49)         (49)                                   
      Accessory Adrenal Cortical Nodule                1 (2%)       1 (2%)                                                          
      Cyst                                                                       1 (2%)       1 (2%)                                
      Cytoplasmic Alteration, Focal                    5 (10%)     11 (22%)      8 (16%)     18 (37%)                               
      Hyperplasia, Focal                               3 (6%)       1 (2%)       3 (6%)       5 (10%)                               
      Hypertrophy, Focal                              10 (20%)     17 (35%)      8 (16%)      7 (14%)                               
      Inflammation, Chronic, Focal                                               1 (2%)                                             
      Capsule, Hyperplasia, Focal                      3 (6%)                    2 (4%)       1 (2%)                                
   Adrenal Medulla                                    (50)         (49)         (48)         (49)                                   
      Hyperplasia                                                   1 (2%)       1 (2%)                                             
   Parathyroid Gland                                  (46)         (45)         (45)         (49)                                   
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page    9                                                              
NTP Experiment-Test: 89006-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                                AZT                                            Date: 05/31/96  
Route: GAVAGE                                                                                                     Time: 12:30:48  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          VEHICLE      30 MG/KG     60 MG/KG     120                                       
                                                   CONTROL                                MG/KG                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
ENDOCRINE SYSTEM - CONT                                                                                                             
      Cyst                                             1 (2%)                    1 (2%)       1 (2%)                                
   Pituitary Gland                                    (40)         (46)         (42)         (47)                                   
      Pars Distalis, Cyst                              1 (3%)       2 (4%)       1 (2%)       3 (6%)                                
      Pars Distalis, Cytoplasmic Alteration, Focal                                            1 (2%)                                
      Pars Distalis, Hyperplasia, Focal                                                       1 (2%)                                
   Thyroid Gland                                      (50)         (49)         (48)         (50)                                   
      Degeneration, Cystic, Focal                     15 (30%)     18 (37%)     11 (23%)     16 (32%)                               
      Follicle, Cyst                                   8 (16%)      4 (8%)       2 (4%)       5 (10%)                               
      Follicular Cell, Hyperplasia                     8 (16%)     10 (20%)     11 (23%)      9 (18%)                               
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENERAL BODY SYSTEM                                                                                                                
                                                                                                                                    
   None                                                                                                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 GENITAL SYSTEM                                                                                                                     
                                                                                                                                    
   Epididymis                                         (50)         (49)         (50)         (50)                                   
      Granuloma Sperm                                  1 (2%)                                                                       
      Spermatocele                                     1 (2%)       1 (2%)                                                          
   Preputial Gland                                    (48)         (50)         (50)         (49)                                   
      Degeneration, Cystic                            39 (81%)     46 (92%)     44 (88%)     45 (92%)                               
      Inflammation, Chronic                            4 (8%)       5 (10%)      2 (4%)                                             
   Prostate                                           (50)         (49)         (50)         (50)                                   
      Inflammation, Chronic                                         3 (6%)                                                          
      Inflammation, Chronic, Focal                     3 (6%)                                 2 (4%)                                
      Epithelium, Hyperplasia, Focal                   2 (4%)                                 1 (2%)                                
   Seminal Vesicle                                    (50)         (49)         (50)         (50)                                   
      Angiectasis                                      1 (2%)       1 (2%)                    4 (8%)                                
      Congestion                                       1 (2%)                                                                       
      Inflammation, Chronic                            1 (2%)                                 1 (2%)                                
   Testes                                             (50)         (49)         (50)         (50)                                   
      Germinal Epithelium, Degeneration                1 (2%)       1 (2%)                    1 (2%)                                
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 HEMATOPOIETIC SYSTEM                                                                                                               
                                                                                                                                    
   Bone Marrow                                        (50)         (50)         (49)         (50)                                   
      Angiectasis                                                   1 (2%)       1 (2%)       1 (2%)                                
      Hyperplasia                                      2 (4%)       6 (12%)      6 (12%)      1 (2%)                                
   Lymph Node                                         (6)          (7)          (5)          (1)                                    
      Inguinal, Hyperplasia, Lymphoid                                            1 (20%)                                            
      Inguinal, Pigmentation                           1 (17%)      2 (29%)      1 (20%)                                            
      Mediastinal, Hyperplasia, Lymphoid               1 (17%)                   1 (20%)                                            
      Mediastinal, Inflammation, Granulomatous         1 (17%)                                                                      
      Pancreatic, Hyperplasia, Lymphoid                1 (17%)                                                                      
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   10                                                              
NTP Experiment-Test: 89006-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                                AZT                                            Date: 05/31/96  
Route: GAVAGE                                                                                                     Time: 12:30:48  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          VEHICLE      30 MG/KG     60 MG/KG     120                                       
                                                   CONTROL                                MG/KG                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
HEMATOPOIETIC SYSTEM - CONT                                                                                                         
   Lymph Node, Mandibular                             (49)         (48)         (49)         (50)                                   
      Hemorrhage                                                    1 (2%)                                                          
      Hyperplasia, Histiocytic                                                                1 (2%)                                
      Hyperplasia, Lymphoid                                         1 (2%)       1 (2%)       1 (2%)                                
      Infiltration Cellular, Mast Cell                                           1 (2%)                                             
   Lymph Node, Mesenteric                             (48)         (49)         (49)         (49)                                   
      Ectasia                                          5 (10%)      4 (8%)       1 (2%)       3 (6%)                                
      Fibrosis                                         1 (2%)                                                                       
      Hemorrhage                                      20 (42%)     31 (63%)     21 (43%)     25 (51%)                               
      Hyperplasia, Lymphoid                            3 (6%)       3 (6%)       3 (6%)       4 (8%)                                
      Inflammation, Granulomatous                      1 (2%)                                                                       
   Spleen                                             (50)         (49)         (48)         (50)                                   
      Angiectasis                                      1 (2%)                                                                       
      Depletion Cellular                               1 (2%)                    1 (2%)       6 (12%)                               
      Hematopoietic Cell Proliferation                18 (36%)     16 (33%)     14 (29%)     11 (22%)                               
      Hyperplasia, Lymphoid                            2 (4%)       1 (2%)       2 (4%)       2 (4%)                                
      Necrosis, Focal                                               1 (2%)                                                          
   Thymus                                             (41)         (44)         (41)         (35)                                   
      Cyst                                             6 (15%)     11 (25%)      5 (12%)      4 (11%)                               
      Mineralization                                                1 (2%)                                                          
      Necrosis                                                                   1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 INTEGUMENTARY SYSTEM                                                                                                               
                                                                                                                                    
   Mammary Gland                                      (15)         (10)         (15)         (5)                                    
      Inflammation, Chronic                                         1 (10%)                                                         
   Skin                                               (50)         (50)         (50)         (50)                                   
      Subcutaneous Tissue, Edema                                    1 (2%)                                                          
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 MUSCULOSKELETAL SYSTEM                                                                                                             
                                                                                                                                    
   Bone                                               (50)         (50)         (50)         (50)                                   
      Hyperostosis                                    30 (60%)     36 (72%)     28 (56%)     41 (82%)                               
   Skeletal Muscle                                    (50)         (50)         (50)         (50)                                   
      Necrosis                                                                   1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 NERVOUS SYSTEM                                                                                                                     
                                                                                                                                    
   Brain                                              (50)         (50)         (49)         (50)                                   
      Hemorrhage                                                    1 (2%)                                                          
   Spinal Cord                                        (1)          (1)                                                              
      Degeneration                                     1 (100%)                                                                     
      Hemorrhage, Focal                                1 (100%)                                                                     
____________________________________________________________________________________________________________________________________
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   11                                                              
NTP Experiment-Test: 89006-06         INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a)               Report: PEIRPT03
Study Type: CHRONIC                                                AZT                                            Date: 05/31/96  
Route: GAVAGE                                                                                                     Time: 12:30:48  
____________________________________________________________________________________________________________________________________
         B6C3F1 MICE MALE                          VEHICLE      30 MG/KG     60 MG/KG     120                                       
                                                   CONTROL                                MG/KG                                     
____________________________________________________________________________________________________________________________________
                                                                                                                                    
                                                                                                                                    
 RESPIRATORY SYSTEM                                                                                                                 
                                                                                                                                    
   Lung                                               (50)         (50)         (50)         (50)                                   
      Hemorrhage                                       2 (4%)       1 (2%)       2 (4%)       3 (6%)                                
      Hyperplasia, Histiocytic                         2 (4%)       2 (4%)       1 (2%)                                             
      Hyperplasia, Lymphoid                                                      1 (2%)                                             
      Infiltration Cellular, Mixed Cell                             1 (2%)       1 (2%)       1 (2%)                                
      Inflammation, Chronic                                         1 (2%)       1 (2%)       1 (2%)                                
      Alveolar Epithelium, Hyperplasia                 6 (12%)      3 (6%)       1 (2%)       8 (16%)                               
   Nose                                               (50)         (50)         (49)         (50)                                   
      Nasolacrimal Duct, Inflammation, Suppurative                               1 (2%)                                             
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 SPECIAL SENSES SYSTEM                                                                                                              
                                                                                                                                    
   Eye                                                                                       (1)                                    
      Cornea, Inflammation, Chronic                                                           1 (100%)                              
   Harderian Gland                                    (3)          (7)          (2)          (10)                                   
      Hyperplasia, Focal                                            1 (14%)                                                         
____________________________________________________________________________________________________________________________________
                                                                                                                                    
 URINARY SYSTEM                                                                                                                     
                                                                                                                                    
   Kidney                                             (50)         (48)         (49)         (50)                                   
      Cyst                                             2 (4%)                    1 (2%)                                             
      Infarct                                          1 (2%)       2 (4%)       1 (2%)       2 (4%)                                
      Metaplasia, Focal, Osseous                       1 (2%)       3 (6%)                    1 (2%)                                
      Nephropathy                                     45 (90%)     44 (92%)     44 (90%)     49 (98%)                               
      Thrombosis                                                                              1 (2%)                                
      Papilla, Necrosis                                                                       1 (2%)                                
      Pelvis, Dilatation                                            1 (2%)                                                          
      Renal Tubule, Accumulation, Hyaline Droplet                   1 (2%)                                                          
      Renal Tubule, Dilatation                                      1 (2%)                    1 (2%)                                
      Renal Tubule, Hyperplasia, Focal                              1 (2%)                                                          
      Renal Tubule, Pigmentation                       2 (4%)                    1 (2%)       1 (2%)                                
   Urethra                                            (1)          (1)                       (1)                                    
      Inflammation, Chronic                            1 (100%)     1 (100%)                  1 (100%)                              
   Urinary Bladder                                    (50)         (50)         (50)         (50)                                   
      Hemorrhage                                       1 (2%)                                                                       
                                                                                                                                    
a  Number of animals examined microscopically at site and number of animals with lesion                                             
                                                             Page   12                                                              
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                             ----------              END OF REPORT             ----------                                           
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NTP is located at the National Institute of Environmental Health Sciences, part of the National Institutes of Health.