Liver cell proliferation induced by single administration of thiobenzamide.

After administration of thiobenzamide (TB) (2.5 mg/100 g b.w.) by stomach tube to male rats, an increase of liver weight was evident within 2 days. It was associated with an increase of hepatic DNA, in the incorporation of [3H]thymidine into nuclei of both hepatocytes and bile duct cells and also in the mitotic index of both types of cells. Liver water content and morphology as well as serum GPT activity were unchanged. In conclusion, TB administration in a single dose below the necrotic threshold stimulates multiplication of liver cells without evidence of damage.