Table 6.
Summary of non‐neoplastic lesions in male rats taken from NCTR (2015)
| Lesion | Dosage (mg/kg bw per day) | Incidence/time of assessmenta | ||
|---|---|---|---|---|
| 36 weeks | 60 weeks | 104 weeks | ||
| Cholangiofibrosis |
0 0.02 0.044 0.092 0.2 0.44 0.92 2 |
0/20 0/20 0/20 0/20 0/20 6/20*** 17/20*** 19/20*** |
0/20 0/10 0/10 0/10 0/10 10/10*** 10/10*** 8/10*** |
0/149 0/150 0/99 1/100 38/50*** 49/49*** 47/50*** 49/49*** |
| Oval cell hyperplasia |
0 0.02 0.044 0.092 0.2 0.44 0.92 2 |
0/20 0/20 0/20 0/20 0/20 0/20 1/20 16/20*** |
0/20 0/10 0/10 0/10 0/10 0/10 3/10* 7/10*** |
14/149 15/150 10/99 8/100 7/50 6/49 14/50*** 33/49*** |
| Mixed cell foci |
0 0.02 0.044 0.092 0.2 0.44 0.92 2 |
0/20 0/20 0/20 0/20 1/20 0/20 1/20 5/20* |
1/20 0/10 1/10 0/10 1/10 1/10 3/10 6/10** |
7/149 7/150 6/99 3/100 5/50 3/49 6/50 13/49*** |
| Biliary tract hyperplasia |
0 0.02 0.044 0.092 0.2 0.44 0.92 2 |
1/20 1/20 0/20 1/20 0/20 0/20 6/20* 19/20*** |
7/20 3/10 1/10 2/10 1/10 2/10 3/10 8/10* |
89/149 86/150 5,999 56/100 29/50 25/49 32/50 43/49*** |
| Bile duct subcapsular hyperplasia |
0 0.02 0.044 0.092 0.2 0.44 0.92 2 |
0/20 0/20 0/20 0/20 1/20 12/20*** 19/20*** 20/20*** |
0/20 0/10 0/10 0/10 1/10 9/10*** 10/10*** 7/10*** |
– |
| Hepatocyte hypertrophy |
0 0.02 0.044 0.092 0.2 0.44 0.92 2 |
0/20 0/20 0/20 0/20 1/20 0/20 2/20 12/20*** |
0/20 0/10 0/10 0/10 0/10 5/10** 4/10** 8/10*** |
– |
| Periportal cytoplasmic alteration |
0 0.02 0.044 0.092 0.2 0.44 0.92 2 |
0/20 0/20 0/20 0/20 0/20 0/20 7/20** 19/20*** |
0/20 0/10 0/10 1/10 0/10 1/10 7/10*** 8/10*** |
– |
| Subcapsular fibrosis |
0 0.02 0.044 0.092 0.2 0.44 0.92 2 |
0/20 0/20 0/20 0/20 3/20 14/20*** 20/20*** 20/20*** |
0/20 0/10 0/10 0/10 4/10** 9/10** 10/10** 7/10*** |
– |
| Subcapsular chronic inflammation |
0 0.02 0.044 0.092 0.2 0.44 0.92 2 |
0/20 0/20 0/20 0/20 2/20 14/20*** 20/20*** 20/20*** |
0/20 0/10 0/10 0/10 8/10*** 9/10** 10/10** 7/10*** |
– |
| Subcapsular pigmentation |
0 0.02 0.044 0.092 0.2 0.44 0.92 2 |
0/20 0/20 0/20 0/20 2/20 14/20*** 20/20*** 20/20*** |
0/20 0/10 0/10 0/10 8/10*** 9/10** 10/10** 7/10*** |
– |
| Basophilic foci |
0 0.02 0.044 0.092 0.2 0.44 0.92 2 |
– | – |
28/149 16/150 19/99 18/100 11/50 13/49 10/50 21/49*** |
| Regenerative hyperplasia |
0 0.02 0.044 0.092 0.2 0.44 0.92 2 |
– | – |
0/149 1/150 1/99 2/100 1/50 1/49 7/50*** 12/49*** |
| Cytoplasmic vacuolisation |
0 0.02 0.044 0.092 0.2 0.44 0.92 2 |
– | – |
23/149 23/150 14/99 19/100 12/50 18/49*** 23/50*** 37/49*** |
bw: body weight.
*Equals significant at > 0.05; **equals significant at > 0.01; ***equals significant at > 0.001.