Effect of cadmium on liver regeneration after partial hepatectomy in rats.

Cadmium is a nonabundant element that is widely distributed throughout the biosphere and its toxic effects are becoming potentially more serious due to industrialization. It has been reported that cadmium might interact with nucleic acid biosynthesis. In this study we examined the effect of cadmium administration, either 24 hr before or simultaneously to partial hepatectomy, on the liver regenerative process in rats, at different time intervals. The rate of DNA synthesis was suppressed markedly in the cadmium pretreated group and the first peak of liver regeneration was delayed, compared to the simply partially hepatectomized one. The administration of cadmium simultaneously to partial hepatectomy, caused a marked decrease of the rate of DNA biosynthesis, compared to the pretreatment. The rate-determining enzyme thymidine kinase was suppressed in the liver of both cadmium-treated groups. Biochemical parameters and histological findings were also coestimated. The above data suggest that either pre- or simultaneous administration of cadmium, suppressed the liver regenerative process, probably due to the inhibition of thymidine kinase.