Effect of subchronic treatment with some heavy metal salts on the activity of the drug metabolizing enzyme system in female rats.

In experiments on female albino rats the effect of 30-day treatment with salts of Co, Cd, Ni, Zn and Hg on the liver monooxygenase system was studied. It was found that CdCl2 and HgCl2 significantly decreased the activity of aniline hydroxylase whereas the activity of ethylmorphine-N-demethylase tended to remain almost constant and no significant changes were observed. The cytochrome P-450 level in Zn-treated female rats was decreased while the other metal salts did not change it. The cytochrome b5 levels were relatively stable and there were no significant differences between treated and untreated animals. Co, Cd and Hg decreased the NADPH-dependent lipid peroxidation whereas Ni and Zn did not change it. All metal salts caused no marked alterations in the female rat liver microsomal membrane fluidity.