THE STATE OF PRO/-ANTIOXIDANT ENZYMES AND HISTOLOGICAL CHANGES IN RAT KIDNEYS UNDER SUBLIMATE-INDUCED DAMAGE

The activity of catalase and glutathione peroxidase in the kidneys of rats was studied 72 hours after administering a 5 mg/kg body weight dose of mercury dichloride solution. This research is important for understanding the effects of mercury salts on the antioxidant system of the kidneys under induced diuresis. In the post-nuclear supernatants of kidney layers, the following were determined: the content of TBA-reactive substances (TBARS); the level of protein oxidative modification products (POMP); and the activities of catalase and glutathione peroxidase. Histological sections were stained with hematoxylin and eosin for the morphological evaluation. A decrease in glutathione peroxidase activity was found in the cortical, medullary, and papillary regions of the kidneys under water and salt loading after mercury dichloride exposure. This was accompanied by an increase in lipid and protein oxidative modification products and morphological changes in kidney tissues. The intensification of oxidative protein and lipid modification in kidney tissues under mercury dichloride action, in our opinion, is associated with the sharp suppression of antioxidant defense enzymes in the kidneys. Specifically, the glutathione peroxidase activity in the kidneys of animals administered HgCl2 decreased by an average of threefold across all kidney layers. The results indicate the suppression of antioxidant defense enzymes in rat kidneys due to mercury dichloride exposure. Keywords: glutathione peroxidase, catalase, protein oxidative modification products, TBA-reactive products, sublimate, kidneys.