The effect of different vitamin a status on cytochrome P-450 content in rat liver

Abstract

The possible effects of different vitamin A status on the liver cytochrome P-450 content were studied in young Wistar rats. It was shown, that both severe conventional deficiency of retinol and rapid synchronous vitamin A deficiency resulted in great decrease of cytochrome P-450 hepatic level. Synchronous vitamin A deficiency didn't induce, however, any significant shifts in microsomal cytochrome b 5 and total protein contents. Mild vitamin A dificiency increased cytochrome P-450 turnover rate in liver microsomes, estimated with 4- 14C-5-aminolevulinic acid as labeled precursor of the hemoprotein. High doses of vitamin A (1200 I.U. per rat during 8 days) and its megadoses (50000 I.U. per rat during 5 days) didn't cause any significant changes in cytochrome P-450 liver content. It is concluded that adequate food supply of vitamin A and its sufficient liver stores are one of the necessary conditions for maintaining normal cytochrome P-450 level in the liver.