EFFECT OF CISPLATIN ON THE ACTIVITIES OF ENZYMES WHICH PROTECT AGAINST LIPID-PEROXIDATION

Increases in lipid peroxide in kidneys of rats treated with cisplatin were examined in relation to decreases in the activities of Cu,Zn-superoxide dismutase (Cu,Zn-SOD), Mn-SOD, glutathione peroxidase (GSHpx), glutathione S-transferase (GST) and catalase. The activities of catalase, GSHpx and GST in the kidney and the liver were significantly decreased after cisplatin administration. The decrease of GST activity in the kidney was 87.3%, this was the largest decrease among these enzymes in the tissues examined. Cu,Zn-SOD activity significantly decreased only in the kidney. In contrast, the activities of these enzymes in the heart and the lung, which showed no increase in lipid peroxide in our previous study, were not significantly decreased. Cisplatin does not directly increase lipid peroxidation in vitro; therefore, the increase of lipid peroxide in the kidneys of these rats treated with cisplatin can be attributed to a decrease in the activities of lipid peroxide-protecting enzymes.