NTP Experiment-Test: 55301-04 INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a) Report: PEIRPT03
Study Type: CHRONIC PYRIDINE Date: 11/19/96
Route: DOSED WATER Time: 14:46:10
CORE STUDY
Facility: TSI Mason Research
Chemical CAS #: 110-86-1
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: 55301-04 INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a) Report: PEIRPT03
Study Type: CHRONIC PYRIDINE Date: 11/19/96
Route: DOSED WATER Time: 14:46:10
____________________________________________________________________________________________________________________________________
B6C3F1 MICE FEMALE 0 PPM 125 PPM 250 PPM 500 PPM
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY
Animals Initially In Study 50 50 50 50
Early Deaths
Natural Death 12 12 21 11
Accidently Killed 3 6 4 5
Moribund Sacrifice 3 2 3 5
Survivors
Terminal Sacrifice 32 30 22 29
Animals Examined Microscopically 50 50 50 50
____________________________________________________________________________________________________________________________________
ALIMENTARY SYSTEM
Gallbladder (37) (40) (33) (34)
Hyperplasia 1 (3%)
Intestine Large, Rectum (44) (48) (47) (47)
Artery, Necrosis 1 (2%)
Intestine Large, Cecum (44) (49) (40) (45)
Edema 1 (3%)
Intestine Small, Jejunum (42) (47) (38) (43)
Peyer's Patch, Hyperplasia, Lymphoid 1 (2%)
Intestine Small, Ileum (43) (48) (37) (41)
Peyer's Patch, Hyperplasia, Lymphoid 1 (2%)
Liver (49) (50) (50) (50)
Basophilic Focus 1 (2%)
Clear Cell Focus 1 (2%) 5 (10%) 1 (2%) 2 (4%)
Cyst 1 (2%)
Eosinophilic Focus 17 (35%) 12 (24%) 14 (28%) 9 (18%)
Hematopoietic Cell Proliferation 2 (4%) 1 (2%) 1 (2%) 1 (2%)
Hemorrhage 1 (2%)
Infiltration Cellular, Lymphocyte 4 (8%)
Mixed Cell Focus 5 (10%) 4 (8%) 3 (6%)
Necrosis 5 (10%) 2 (4%) 5 (10%) 7 (14%)
Vacuolization Cytoplasmic, Diffuse 1 (2%) 1 (2%)
Centrilobular, Congestion 1 (2%)
Centrilobular, Degeneration 1 (2%) 1 (2%)
Midzonal, Vacuolization Cytoplasmic 1 (2%)
Periportal, Vacuolization Cytoplasmic 2 (4%) 1 (2%)
Mesentery (17) (18) (13) (13)
Infiltration Cellular, Lymphocyte 1 (6%)
Inflammation, Chronic Active 2 (12%)
Fat, Necrosis 12 (71%) 13 (72%) 11 (85%) 9 (69%)
Pancreas (49) (49) (47) (48)
Infiltration Cellular, Lymphocyte 1 (2%) 1 (2%)
Inflammation, Chronic Active 1 (2%) 2 (4%)
Acinus, Atrophy 2 (4%) 1 (2%) 2 (4%)
a Number of animals examined microscopically at site and number of animals with lesion
Page 2
NTP Experiment-Test: 55301-04 INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a) Report: PEIRPT03
Study Type: CHRONIC PYRIDINE Date: 11/19/96
Route: DOSED WATER Time: 14:46:10
____________________________________________________________________________________________________________________________________
B6C3F1 MICE FEMALE 0 PPM 125 PPM 250 PPM 500 PPM
____________________________________________________________________________________________________________________________________
ALIMENTARY SYSTEM - CONT
Artery, Inflammation, Chronic 1 (2%)
Duct, Cyst 1 (2%) 2 (4%) 2 (4%)
Salivary Glands (50) (50) (49) (50)
Infiltration Cellular, Lymphocyte 33 (66%) 35 (70%) 36 (73%) 29 (58%)
Stomach, Forestomach (49) (49) (49) (49)
Ulcer 1 (2%)
Epithelium, Hyperplasia 1 (2%)
Stomach, Glandular (48) (49) (48) (49)
Necrosis 3 (6%) 3 (6%) 4 (8%) 3 (6%)
Tooth (2)
Developmental Malformation 2 (100%)
____________________________________________________________________________________________________________________________________
CARDIOVASCULAR SYSTEM
Blood Vessel (48) (47) (47) (47)
Aorta, Inflammation, Chronic Active 1 (2%)
Heart (50) (50) (50) (50)
Cardiomyopathy 1 (2%)
Inflammation, Chronic Active 1 (2%)
Mineralization 1 (2%)
Atrium, Thrombosis 1 (2%)
____________________________________________________________________________________________________________________________________
ENDOCRINE SYSTEM
Adrenal Cortex (49) (50) (48) (50)
Cytoplasmic Alteration 2 (4%) 2 (4%)
Hematopoietic Cell Proliferation 1 (2%) 1 (2%)
Hemorrhage 1 (2%) 2 (4%)
Hyperplasia 1 (2%)
Capsule, Hyperplasia 41 (84%) 35 (70%) 39 (81%) 37 (74%)
Adrenal Medulla (49) (49) (45) (49)
Hyperplasia 1 (2%) 2 (4%)
Islets, Pancreatic (49) (50) (47) (49)
Hyperplasia 2 (4%) 3 (6%)
Parathyroid Gland (31) (29) (30) (36)
Infiltration Cellular, Lymphocyte 1 (3%)
Pituitary Gland (47) (44) (42) (46)
Hemorrhage 1 (2%)
Pars Distalis, Angiectasis 1 (2%) 1 (2%)
Pars Distalis, Hyperplasia 5 (11%) 4 (9%) 6 (14%) 8 (17%)
Pars Intermedia, Hyperplasia 1 (2%)
Thyroid Gland (50) (50) (50) (50)
Infiltration Cellular, Lymphocyte 3 (6%) 3 (6%)
C-Cell, Hyperplasia 1 (2%)
Follicle, Cyst 4 (8%) 1 (2%)
a Number of animals examined microscopically at site and number of animals with lesion
Page 3
NTP Experiment-Test: 55301-04 INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a) Report: PEIRPT03
Study Type: CHRONIC PYRIDINE Date: 11/19/96
Route: DOSED WATER Time: 14:46:10
____________________________________________________________________________________________________________________________________
B6C3F1 MICE FEMALE 0 PPM 125 PPM 250 PPM 500 PPM
____________________________________________________________________________________________________________________________________
ENDOCRINE SYSTEM - CONT
Follicular Cell, Hyperplasia 14 (28%) 21 (42%) 22 (44%) 23 (46%)
____________________________________________________________________________________________________________________________________
GENERAL BODY SYSTEM
Peritoneum (2)
Inflammation, Chronic Active 1 (50%)
____________________________________________________________________________________________________________________________________
GENITAL SYSTEM
Clitoral Gland (47) (48) (48) (45)
Atrophy 45 (96%) 43 (90%) 45 (94%) 43 (96%)
Cyst 3 (6%)
Inflammation, Chronic 2 (4%) 2 (4%) 1 (2%) 4 (9%)
Inflammation, Chronic Active 2 (4%) 3 (6%)
Pigmentation 2 (4%) 1 (2%) 3 (7%)
Ovary (47) (49) (46) (49)
Angiectasis 1 (2%)
Cyst 14 (30%) 9 (18%) 11 (24%) 11 (22%)
Periovarian Tissue, Hyperplasia, Lymphoid 1 (2%)
Uterus (48) (50) (47) (50)
Congestion 1 (2%)
Cyst 3 (6%) 3 (6%) 5 (11%) 2 (4%)
Hyperplasia, Cystic 44 (92%) 43 (86%) 38 (81%) 39 (78%)
Inflammation, Chronic Active 1 (2%) 1 (2%)
Pigmentation 1 (2%)
____________________________________________________________________________________________________________________________________
HEMATOPOIETIC SYSTEM
Bone Marrow (49) (50) (49) (50)
Atrophy 1 (2%) 1 (2%)
Myeloid Cell, Hyperplasia 1 (2%) 2 (4%)
Lymph Node (10) (10) (7) (7)
Iliac, Hemorrhage 1 (10%)
Iliac, Hyperplasia, Lymphoid 3 (30%) 2 (29%)
Iliac, Inflammation, Chronic Active 1 (14%)
Iliac, Pigmentation 1 (10%)
Inguinal, Hyperplasia, Lymphoid 1 (14%)
Mediastinal, Hemorrhage 1 (10%) 1 (14%)
Mediastinal, Hyperplasia, Plasma Cell 1 (10%)
Mediastinal, Inflammation, Chronic Active 1 (10%)
Mediastinal, Pigmentation 1 (14%)
Renal, Hemorrhage 1 (14%)
Renal, Hyperplasia, Lymphoid 1 (10%)
Lymph Node, Mandibular (48) (50) (49) (47)
a Number of animals examined microscopically at site and number of animals with lesion
Page 4
NTP Experiment-Test: 55301-04 INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a) Report: PEIRPT03
Study Type: CHRONIC PYRIDINE Date: 11/19/96
Route: DOSED WATER Time: 14:46:10
____________________________________________________________________________________________________________________________________
B6C3F1 MICE FEMALE 0 PPM 125 PPM 250 PPM 500 PPM
____________________________________________________________________________________________________________________________________
HEMATOPOIETIC SYSTEM - CONT
Hemorrhage 3 (6%) 1 (2%) 1 (2%)
Hyperplasia, Lymphoid 2 (4%) 2 (4%)
Lymph Node, Mesenteric (48) (47) (43) (45)
Angiectasis 1 (2%) 2 (4%)
Ectasia 1 (2%)
Hematopoietic Cell Proliferation 1 (2%) 1 (2%)
Hemorrhage 4 (8%) 2 (4%) 3 (7%) 2 (4%)
Hyperplasia, Lymphoid 1 (2%) 1 (2%)
Artery, Necrosis 1 (2%)
Spleen (49) (50) (48) (49)
Atrophy 1 (2%) 1 (2%)
Hematopoietic Cell Proliferation 29 (59%) 27 (54%) 32 (67%) 39 (80%)
Hemorrhage 1 (2%) 1 (2%)
Hyperplasia, Lymphoid 2 (4%) 5 (10%) 4 (8%) 2 (4%)
Inflammation, Chronic Active 1 (2%)
Pigmentation 1 (2%) 1 (2%)
Thymus (45) (44) (46) (39)
Atrophy 11 (24%) 11 (25%) 13 (28%) 10 (26%)
Ectopic Parathyroid Gland 1 (2%) 2 (4%)
Hyperplasia, Lymphoid 1 (2%) 1 (2%)
Inflammation, Acute 1 (2%)
Necrosis 2 (4%) 4 (9%) 3 (7%) 3 (8%)
____________________________________________________________________________________________________________________________________
INTEGUMENTARY SYSTEM
Mammary Gland (47) (50) (49) (48)
Hyperplasia 2 (4%) 1 (2%)
Skin (49) (50) (50) (50)
Inflammation, Chronic Active 1 (2%) 1 (2%) 1 (2%) 1 (2%)
Subcutaneous Tissue, Necrosis 1 (2%)
____________________________________________________________________________________________________________________________________
MUSCULOSKELETAL SYSTEM
Bone (50) (50) (50) (50)
Fibrous Osteodystrophy 5 (10%) 2 (4%)
Hyperostosis 1 (2%)
____________________________________________________________________________________________________________________________________
NERVOUS SYSTEM
Brain (50) (50) (50) (50)
Cyst Epithelial Inclusion 1 (2%)
Hemorrhage 1 (2%) 1 (2%)
Infiltration Cellular, Histiocyte 1 (2%)
Mineralization 25 (50%) 27 (54%) 18 (36%) 19 (38%)
a Number of animals examined microscopically at site and number of animals with lesion
Page 5
NTP Experiment-Test: 55301-04 INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a) Report: PEIRPT03
Study Type: CHRONIC PYRIDINE Date: 11/19/96
Route: DOSED WATER Time: 14:46:10
____________________________________________________________________________________________________________________________________
B6C3F1 MICE FEMALE 0 PPM 125 PPM 250 PPM 500 PPM
____________________________________________________________________________________________________________________________________
NERVOUS SYSTEM - CONT
Meninges, Inflammation, Chronic Active 1 (2%)
____________________________________________________________________________________________________________________________________
RESPIRATORY SYSTEM
Lung (50) (50) (50) (50)
Congestion 2 (4%) 4 (8%) 3 (6%)
Hemorrhage 1 (2%) 1 (2%)
Infiltration Cellular, Lymphocyte 4 (8%) 2 (4%) 1 (2%)
Inflammation, Chronic Active 1 (2%)
Alveolar Epithelium, Hyperplasia 5 (10%) 3 (6%) 1 (2%)
Alveolus, Infiltration Cellular, Histiocyte 2 (4%) 2 (4%)
Nose (50) (50) (47) (50)
Foreign Body 1 (2%)
Olfactory Epithelium, Degeneration, Hyaline 19 (38%) 27 (54%) 35 (74%) 36 (72%)
Olfactory Epithelium, Inflammation, Chronic
Active 1 (2%)
Olfactory Epithelium, Necrosis 1 (2%)
Respiratory Epithelium, Degeneration, Hyaline 26 (52%) 16 (32%) 12 (26%) 13 (26%)
Respiratory Epithelium, Hyperplasia 12 (24%) 8 (16%) 12 (26%) 4 (8%)
Respiratory Epithelium, Inflammation,
Chronic Active 3 (6%) 1 (2%)
Respiratory Epithelium, Necrosis 1 (2%)
____________________________________________________________________________________________________________________________________
SPECIAL SENSES SYSTEM
None
____________________________________________________________________________________________________________________________________
URINARY SYSTEM
Kidney (49) (50) (49) (49)
Infarct 1 (2%) 2 (4%) 1 (2%)
Infiltration Cellular, Plasma Cell 1 (2%)
Infiltration Cellular, Lymphocyte 4 (8%) 2 (4%) 5 (10%) 2 (4%)
Nephropathy 5 (10%) 10 (20%) 7 (14%) 8 (16%)
Glomerulus, Amyloid Deposition 1 (2%)
Renal Tubule, Dilatation 1 (2%) 2 (4%) 2 (4%)
Renal Tubule, Pigmentation 3 (6%) 2 (4%)
Renal Tubule, Regeneration 1 (2%) 1 (2%)
Urinary Bladder (45) (49) (44) (43)
a Number of animals examined microscopically at site and number of animals with lesion
Page 6
NTP Experiment-Test: 55301-04 INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a) Report: PEIRPT03
Study Type: CHRONIC PYRIDINE Date: 11/19/96
Route: DOSED WATER Time: 14:46:10
____________________________________________________________________________________________________________________________________
B6C3F1 MICE FEMALE 0 PPM 125 PPM 250 PPM 500 PPM
____________________________________________________________________________________________________________________________________
URINARY SYSTEM - CONT
Infiltration Cellular, Lymphocyte 16 (36%) 16 (33%) 17 (39%) 22 (51%)
a Number of animals examined microscopically at site and number of animals with lesion
Page 7
NTP Experiment-Test: 55301-04 INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a) Report: PEIRPT03
Study Type: CHRONIC PYRIDINE Date: 11/19/96
Route: DOSED WATER Time: 14:46:10
____________________________________________________________________________________________________________________________________
B6C3F1 MICE MALE 0 PPM 250 PPM 500 PPM 1000 PPM
____________________________________________________________________________________________________________________________________
DISPOSITION SUMMARY
Animals Initially In Study 50 50 50 50
Early Deaths
Natural Death 11 18 11 11
Accidently Killed 2 1 1 3
Moribund Sacrifice 2 3 3 1
Survivors
Natural Death 1
Terminal Sacrifice 35 28 34 35
Animals Examined Microscopically 50 50 49 50
____________________________________________________________________________________________________________________________________
ALIMENTARY SYSTEM
Gallbladder (43) (33) (30) (36)
Hyperplasia 1 (3%)
Infiltration Cellular, Lymphocyte 1 (2%)
Ulcer 1 (3%)
Intestine Large, Colon (48) (48) (46) (50)
Inflammation, Chronic Active 1 (2%)
Intestine Large, Cecum (47) (44) (42) (45)
Lymphoid Tissue, Hyperplasia 2 (5%) 1 (2%)
Lymphoid Tissue, Necrosis 1 (2%)
Intestine Small, Jejunum (40) (46) (42) (44)
Peyer's Patch, Hyperplasia, Lymphoid 1 (3%) 1 (2%) 3 (7%) 1 (2%)
Liver (50) (50) (49) (50)
Angiectasis 1 (2%) 1 (2%)
Basophilic Focus 3 (6%) 1 (2%)
Clear Cell Focus 1 (2%) 3 (6%) 1 (2%) 2 (4%)
Cyst 1 (2%)
Eosinophilic Focus 19 (38%) 22 (44%) 18 (37%) 15 (30%)
Hematopoietic Cell Proliferation 1 (2%) 1 (2%)
Hemorrhage 1 (2%)
Infiltration Cellular, Mixed Cell 1 (2%) 1 (2%) 1 (2%)
Mixed Cell Focus 4 (8%) 2 (4%) 1 (2%) 1 (2%)
Necrosis 3 (6%) 5 (10%) 7 (14%) 6 (12%)
Vacuolization Cytoplasmic, Diffuse 2 (4%) 1 (2%)
Centrilobular, Congestion 1 (2%)
Centrilobular, Hypertrophy 1 (2%)
Centrilobular, Vacuolization Cytoplasmic 1 (2%) 2 (4%) 6 (12%)
Periportal, Vacuolization Cytoplasmic 1 (2%) 2 (4%)
Mesentery (2) (7) (6) (4)
Fat, Necrosis 2 (100%) 3 (43%) 1 (17%) 2 (50%)
Oral Mucosa (1)
Ulcer 1 (100%)
Pancreas (49) (50) (48) (50)
a Number of animals examined microscopically at site and number of animals with lesion
Page 8
NTP Experiment-Test: 55301-04 INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a) Report: PEIRPT03
Study Type: CHRONIC PYRIDINE Date: 11/19/96
Route: DOSED WATER Time: 14:46:10
____________________________________________________________________________________________________________________________________
B6C3F1 MICE MALE 0 PPM 250 PPM 500 PPM 1000 PPM
____________________________________________________________________________________________________________________________________
ALIMENTARY SYSTEM - CONT
Acinus, Atrophy 3 (6%) 2 (4%) 1 (2%) 1 (2%)
Acinus, Cytoplasmic Alteration 1 (2%) 1 (2%)
Duct, Cyst 1 (2%) 1 (2%)
Salivary Glands (48) (50) (49) (50)
Infiltration Cellular, Lymphocyte 31 (65%) 33 (66%) 26 (53%) 34 (68%)
Stomach, Forestomach (49) (50) (48) (49)
Inflammation, Chronic 1 (2%)
Inflammation, Chronic Active 1 (2%) 1 (2%) 2 (4%) 2 (4%)
Ulcer 1 (2%)
Epithelium, Hyperplasia 1 (2%) 2 (4%) 2 (4%)
Stomach, Glandular (49) (50) (48) (47)
Necrosis 2 (4%) 2 (4%) 4 (8%) 1 (2%)
Glands, Dysplasia 2 (4%)
Tooth (42) (10) (1) (3)
Developmental Malformation 42 (100%) 10 (100%) 1 (100%) 3 (100%)
____________________________________________________________________________________________________________________________________
CARDIOVASCULAR SYSTEM
Blood Vessel (50) (49) (47) (49)
Aorta, Thrombosis 1 (2%)
Heart (50) (50) (49) (50)
Cardiomyopathy 1 (2%)
Mineralization 3 (6%)
Thrombosis 1 (2%)
Artery, Inflammation, Chronic Active 2 (4%)
Myocardium, Hypertrophy 1 (2%)
____________________________________________________________________________________________________________________________________
ENDOCRINE SYSTEM
Adrenal Cortex (49) (49) (49) (49)
Cytoplasmic Alteration 18 (37%) 13 (27%) 9 (18%) 11 (22%)
Hyperplasia 2 (4%) 1 (2%) 2 (4%)
Vacuolization Cytoplasmic 2 (4%) 1 (2%)
Capsule, Hyperplasia 42 (86%) 29 (59%) 30 (61%) 29 (59%)
Islets, Pancreatic (49) (50) (48) (50)
Hyperplasia 5 (10%) 2 (4%)
Parathyroid Gland (31) (35) (40) (31)
Cyst 1 (3%) 1 (3%)
Pituitary Gland (46) (47) (45) (49)
Cyst 1 (2%) 1 (2%)
Pars Distalis, Hyperplasia 1 (2%)
Thyroid Gland (49) (50) (49) (50)
Infiltration Cellular, Lymphocyte 1 (2%)
Follicle, Cyst 1 (2%)
Follicular Cell, Hyperplasia 8 (16%) 14 (28%) 20 (41%) 12 (24%)
a Number of animals examined microscopically at site and number of animals with lesion
Page 9
NTP Experiment-Test: 55301-04 INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a) Report: PEIRPT03
Study Type: CHRONIC PYRIDINE Date: 11/19/96
Route: DOSED WATER Time: 14:46:10
____________________________________________________________________________________________________________________________________
B6C3F1 MICE MALE 0 PPM 250 PPM 500 PPM 1000 PPM
____________________________________________________________________________________________________________________________________
GENERAL BODY SYSTEM
None
____________________________________________________________________________________________________________________________________
GENITAL SYSTEM
Epididymis (50) (50) (49) (50)
Angiectasis 1 (2%)
Infiltration Cellular, Lymphocyte 1 (2%) 4 (8%) 4 (8%) 4 (8%)
Inflammation, Granulomatous 1 (2%) 1 (2%) 3 (6%)
Penis (1)
Inflammation, Chronic Active 1 (100%)
Preputial Gland (50) (50) (49) (49)
Atrophy 48 (96%) 45 (90%) 47 (96%) 42 (86%)
Cyst 29 (58%) 25 (50%) 32 (65%) 28 (57%)
Inflammation, Chronic 18 (36%) 18 (36%) 13 (27%) 12 (24%)
Inflammation, Chronic Active 4 (8%) 6 (12%) 3 (6%) 6 (12%)
Prostate (50) (48) (48) (49)
Cyst 1 (2%)
Hyperplasia 1 (2%) 1 (2%)
Inflammation, Chronic 7 (14%) 3 (6%) 10 (21%) 8 (16%)
Inflammation, Chronic Active 1 (2%) 1 (2%)
Testes (50) (50) (49) (50)
Atrophy 2 (4%) 1 (2%) 1 (2%) 1 (2%)
Mineralization 1 (2%)
Interstitial Cell, Hyperplasia 1 (2%)
____________________________________________________________________________________________________________________________________
HEMATOPOIETIC SYSTEM
Bone Marrow (49) (50) (49) (50)
Atrophy 2 (4%)
Erythroid Cell, Hyperplasia 1 (2%)
Myeloid Cell, Hyperplasia 1 (2%) 1 (2%) 1 (2%)
Lymph Node (2) (4) (4) (2)
Iliac, Hyperplasia, Lymphoid 1 (50%)
Mediastinal, Congestion 1 (50%)
Pancreatic, Hyperplasia, Lymphoid 1 (25%)
Renal, Hemorrhage 2 (50%) 1 (50%)
Renal, Necrosis 1 (25%)
Lymph Node, Mandibular (48) (47) (48) (50)
Hyperplasia, Lymphoid 3 (6%) 1 (2%) 1 (2%)
Hyperplasia, Plasma Cell 2 (4%)
Necrosis 1 (2%)
Lymph Node, Mesenteric (43) (47) (44) (50)
Angiectasis 2 (4%)
a Number of animals examined microscopically at site and number of animals with lesion
Page 10
NTP Experiment-Test: 55301-04 INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a) Report: PEIRPT03
Study Type: CHRONIC PYRIDINE Date: 11/19/96
Route: DOSED WATER Time: 14:46:10
____________________________________________________________________________________________________________________________________
B6C3F1 MICE MALE 0 PPM 250 PPM 500 PPM 1000 PPM
____________________________________________________________________________________________________________________________________
HEMATOPOIETIC SYSTEM - CONT
Atrophy 1 (2%)
Hematopoietic Cell Proliferation 2 (5%) 3 (6%) 6 (14%) 1 (2%)
Hemorrhage 13 (30%) 10 (21%) 10 (23%) 12 (24%)
Hyperplasia, Histiocytic 2 (5%) 1 (2%)
Hyperplasia, Lymphoid 1 (2%) 5 (11%) 3 (7%) 4 (8%)
Hyperplasia, Plasma Cell 1 (2%) 1 (2%)
Necrosis 1 (2%)
Spleen (49) (50) (47) (49)
Atrophy 2 (4%) 3 (6%)
Hematopoietic Cell Proliferation 13 (27%) 30 (60%) 26 (55%) 23 (47%)
Hyperplasia, Lymphoid 1 (2%) 1 (2%) 1 (2%)
Necrosis 1 (2%)
Thymus (46) (46) (39) (47)
Atrophy 26 (57%) 21 (46%) 16 (41%) 16 (34%)
Cyst 1 (2%)
Necrosis 1 (3%) 1 (2%)
____________________________________________________________________________________________________________________________________
INTEGUMENTARY SYSTEM
Skin (49) (50) (48) (50)
Inflammation, Chronic Active 1 (2%)
Ulcer 1 (2%)
Subcutaneous Tissue, Edema 1 (2%) 1 (2%)
Subcutaneous Tissue, Inflammation, Acute 1 (2%)
Subcutaneous Tissue, Inflammation, Chronic
Active 1 (2%) 1 (2%)
____________________________________________________________________________________________________________________________________
MUSCULOSKELETAL SYSTEM
None
____________________________________________________________________________________________________________________________________
NERVOUS SYSTEM
Brain (50) (50) (49) (50)
Hemorrhage 1 (2%)
Inflammation, Chronic Active 1 (2%)
Mineralization 41 (82%) 27 (54%) 30 (61%) 35 (70%)
Peripheral Nerve (1) (1)
Sciatic, Degeneration 1 (100%)
____________________________________________________________________________________________________________________________________
a Number of animals examined microscopically at site and number of animals with lesion
Page 11
NTP Experiment-Test: 55301-04 INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a) Report: PEIRPT03
Study Type: CHRONIC PYRIDINE Date: 11/19/96
Route: DOSED WATER Time: 14:46:10
____________________________________________________________________________________________________________________________________
B6C3F1 MICE MALE 0 PPM 250 PPM 500 PPM 1000 PPM
____________________________________________________________________________________________________________________________________
RESPIRATORY SYSTEM
Lung (49) (50) (49) (50)
Congestion 1 (2%) 1 (2%) 1 (2%) 2 (4%)
Hemorrhage 1 (2%)
Infiltration Cellular, Lymphocyte 4 (8%) 2 (4%)
Alveolar Epithelium, Hyperplasia 4 (8%) 8 (16%) 1 (2%) 2 (4%)
Alveolus, Infiltration Cellular, Histiocyte 1 (2%) 2 (4%) 4 (8%) 1 (2%)
Nose (50) (49) (49) (50)
Foreign Body 1 (2%)
Olfactory Epithelium, Degeneration, Hyaline 15 (30%) 31 (63%) 35 (71%) 7 (14%)
Olfactory Epithelium, Glands, Hyperplasia 1 (2%)
Respiratory Epithelium, Degeneration, Hyaline 20 (40%) 10 (20%) 15 (31%) 2 (4%)
Respiratory Epithelium, Hyperplasia 20 (40%) 22 (45%) 11 (22%) 15 (30%)
Respiratory Epithelium, Inflammation,
Chronic Active 2 (4%) 1 (2%) 1 (2%)
____________________________________________________________________________________________________________________________________
SPECIAL SENSES SYSTEM
Eye (1) (1)
Cataract 1 (100%)
Cornea, Inflammation, Chronic 1 (100%)
Cornea, Inflammation, Chronic Active 1 (100%)
____________________________________________________________________________________________________________________________________
URINARY SYSTEM
Kidney (49) (50) (48) (50)
Atrophy 1 (2%)
Cyst 4 (8%) 2 (4%) 4 (8%)
Fibrosis 1 (2%)
Hydronephrosis 1 (2%)
Infarct 2 (4%) 1 (2%) 2 (4%) 6 (12%)
Infiltration Cellular, Lymphocyte 3 (6%) 1 (2%) 2 (4%) 6 (12%)
Inflammation, Chronic Active 2 (4%)
Mineralization 2 (4%) 3 (6%)
Nephropathy 34 (69%) 27 (54%) 25 (52%) 32 (64%)
Artery, Inflammation, Chronic 1 (2%)
Artery, Inflammation, Chronic Active 1 (2%)
Renal Tubule, Accumulation, Hyaline Droplet 1 (2%)
Renal Tubule, Dilatation 1 (2%) 2 (4%) 5 (10%)
Renal Tubule, Hyperplasia 3 (6%) 1 (2%) 1 (2%)
Renal Tubule, Pigmentation 5 (10%) 3 (6%) 2 (4%)
Urinary Bladder (48) (49) (44) (50)
a Number of animals examined microscopically at site and number of animals with lesion
Page 12
NTP Experiment-Test: 55301-04 INCIDENCE RATES OF NONNEOPLASTIC LESIONS BY ANATOMIC SITE (a) Report: PEIRPT03
Study Type: CHRONIC PYRIDINE Date: 11/19/96
Route: DOSED WATER Time: 14:46:10
____________________________________________________________________________________________________________________________________
B6C3F1 MICE MALE 0 PPM 250 PPM 500 PPM 1000 PPM
____________________________________________________________________________________________________________________________________
URINARY SYSTEM - CONT
Infiltration Cellular, Lymphocyte 8 (17%) 7 (14%) 9 (20%) 8 (16%)
a Number of animals examined microscopically at site and number of animals with lesion
Page 13
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