Effect of copper and cadmium pretreatments on DNA synthesis and thymidine kinase activity in the liver of dimethylnitrosamine-treated and partially hepatectomized rats
Sakai, K.; Murata, N.; Yamane, Y.
Gan 74(5): 663-670
1983
ISSN/ISBN: 0016-450X PMID: 6642140 Document Number: 206335
Dose-related suppression of the 3H-thymidine incorporation into liver DNA of rats after a single injection of dimethylnitrosamine by Cu pretreatment was observed. The 3H-thymidine incorporation was not decreased by Cd pretreatment. On the other hand, the 3H-thymidine incorporation into liver DNA of partially hepatectomized rats was decreased by both Cu and Cd pretreatments. Thymidine kinase activity in the liver of rats treated with dimethylnitrosamine was also decreased by Cu pretreatment, but the enzyme activity was not decreased by Cd pretreatment. Cu accumulation in the liver of Cu-administered rats was predominantly in the nuclear fraction, followed by the soluble fraction. Cd accumulation in the liver of Cd-administered rats was predominantly in the soluble fraction, followed by the nuclear fraction. Cu accumulation in the nuclear fraction may suppress the induction of thymidine kinase in the liver of rats by dimethylnitrosamine.