Target Organs and Levels of Evidence for TR-476
Toxicology and Carcinogenesis Studies of Primidone (CASRN 125-33-7) in F344/N Rats and B6C3F1 Mice (Feed Studies)
Chemical (Study Title) CASRN |
Peer Review Date |
Route/Exposure Levels |
Study Laboratory |
Primidone (primaclone) 125-33-7 |
12/12/1996 |
Dosed-Feed M: 0, 0.03, 0.06, OR 0.13% R: 0, 0.06, 0.13, OR 0.25% (50/SEX/SPECIES) |
Battelle Columbus Laboratory |
Levels of Evidence
Male Rats: Equivocal Evidence
Type |
Organ/Tissue (Lesion) |
Neoplastic Lesions |
- Thyroid Gland Follicular Cell: ADENOMA 1/50 1/50 6/49 3/49 OR CARCINOMA 1/50 3/50 1/49 1/49 COMBINED 2/50 4/50 7/49 4/49
- Kidney Tubular Cell: (SINGLE SECTIONS) ADENOMA 2/50 1/50 1/50 1/50 OR CARCINOMA 0/50 0/50 0/50 1/50 COMBINED 2/50 1/50 1/50 2/50; (SINGLE AND STEP SECTIONS) ADENOMA 4/50 2/50 4/50 6/50 OR CARCINOMA 0/50 0/50 0/50 1/50 COMBINED 4/50 2/50 4/50 7/50
|
Non-Neoplastic Lesions |
- LIVER: CYTOPLASMIC VACUOLIZATION; CENTRILOBULAR HYPERTROPHY
- KIDNEY: INCREASED SEVERITY OF NEPHROPATHY; RENAL TUBULE HYPERPLASIA
|
Female Rats: No Evidence
Type |
Organ/Tissue (Lesion) |
Non-Neoplastic Lesions |
- LIVER: CYTOPLASMIC VACUOLIZATION; CENTRILOBULAR HYPERTROPHY; EOSINOPHILIC FOCUS
|
Male Mice: Clear Evidence
Type |
Organ/Tissue (Lesion) |
Neoplastic Lesions |
- Liver: ADENOMA 22/50 41/50 39/50 32/50, CARCINOMA 12/50 31/50 35/50 38/50 OR HEPATOBLASTOMA 0/50 17/50 26/50 7/50 COMBINED 31/50 49/50 49/50 46/50
- Thyroid Gland Follicular Cell: ADENOMA 0/49 3/48 3/50 6/50
|
Non-Neoplastic Lesions |
- LIVER: CENTRILOBULAR HYPERTROPHY
- THYROID GLAND: FOLLICULAR CELL HYPERPLASIA
|
Female Mice: Clear Evidence
Type |
Organ/Tissue (Lesion) |
Neoplastic Lesions |
- Liver: ADENOMA 15/50 42/50 45/49 47/50, CARCINOMA 3/50 11/50 19/49 38/50 OR HEPATOBLASTOMA 1/50 4/50 4/49 4/50 COMBINED 16/50 42/50 46/49 50/50
|
Non-Neoplastic Lesions |
- LIVER: CENTRILOBULAR HYPERTROPHY; CYTOPLASMIC VACUOLIZATION; EOSINOPHILIC FOCUS
- THYROID GLAND: FOLLICULAR CELL HYPERPLASIA
|