Effects of dietary vitamin E and selenium on the mixed-function oxygenase system of male and female chicks

1. 1. Selenium- and vitamin E-depleted chicks were fed diets containing 0 or 0.2 ppm supplemental Se and/or 0 or 100 IU/kg vitamin E for 12 days; phenobarbital or water was administered orally for the final 6 days. 2. 2. Hepatic microsomal MFO activities, cytochrome P450 levels and NADPH-cytochrome c reductase activities were not significantly affected by sex or diet in uninduced chicks. 3. 3. Maximal induction of MFO activity was impaired by combined Se/vitamin E deficiency in male, but not female, chicks. 4. 4. Induction of cytochrome P450 and NADPH-cytochrome c reductase was not significantly affected by diet in male or female chicks. 5. 5. Total glutathione peroxidase activity was increased by phenobarbital treatment; Se-dependent glutathione peroxidase activity was not affected.