Expression of cytochrome P450 isozymes in Syrian hamster after dietary vitamin A supplementation and deficiency.

Expression of hepatic cytochrome P450 isozymes by vitamin A-deficient or -supplemented diet was studied in Syrian hamsters. In male hamsters given a vitamin A-supplemented diet at a level of 250 IU/g-diet for 6 weeks, a marked increase in the activity of testosterone 7 alpha-hydroxylase was observed, accompanied by an elevation in the level of protein immunorelated to CYP2A1. In the hamsters fed a vitamin A-deficient diet for 6 weeks, a decrease was obtained in the total cytochrome P450 content and in the activities of most drug-metabolizing enzymes in livers.