Sex-related differences in selenium-induced alterations in drug action in the rat

Three days after pretreatment of rats of both sexes with sodium selenite (2.4 mg Se/kg, ip) the duration of pentobarbital-induced hypnosis was potentiated in males but not females. Similar treatment with selenium led to a significant inhibition of ethylmorphine demethylase activity by hepatic microsomal enzymes obtained from male but not female rats. Selenium treatment did not alter the activity of aniline hydroxylase in animals of either sex. These data show that there is a sex-related difference in the ability of selenium to alter drug response and hepatic drug metabolism, which is substrate-specific, in the rat.