[The effect of selenium on enzymes metabolizing xenobiotics in rat liver]

Activity of enzymes involved in metabolism of xenobiotics was not altered in liver tissue of rats kept on a ration enriched with selenium at a dose of 2.5 mg/kg. Both organic form of selenium (yeast meal, selenomethionine) and inorganic derivatives (sodium selenite) at a dose of 5 mg/kg of ration caused distinct activation of epoxide hydrolase, UDP-glucuronosyl transferase and glutathione transferase within 6 weeks after the experiment beginning, while content of cytochrome P-450, glutathione-SH and glutathione peroxidase activity were not significantly altered. Within 9 weeks the enzymatic activity remained at the higher rate only in rats kept on the ration with sodium selenite. Relationship between toxic effects of selenium high doses and alterations in activity of enzymes involved in metabolism of xenobiotics is discussed.