Decreased hepatic vitamin A after drug administration in men and in rats.
Eleven patients with moderate drug-induced liver changes were found to have extremely low hepatic vitamin A levels (less than 10% of normal). Their serum vitamin A, retinol-binding protein, and transthyretin were only slightly affected. In rats, two representative drugs (phenobarbital and methylcholanthrene) produced a significant depression of hepatic vitamin A, whereas plasma vitamin A levels remained normal. The livers of drug-treated animals showed no abnormalities except for the expected proliferation of the smooth endoplasmic reticulum and induction of microsomal enzymes and cytochrome P-450 (phenobarbital) and P-448 (methylcholanthrene). These findings suggest that the decrease in hepatic vitamin A may be secondary, at least in part, to enhanced microsomal metabolism.
D000818:Animals; D056486:Chemical and Drug Induced Liver Injury; D006801:Humans; D007668:Kidney / Q000187:drug effects / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D008107:Liver Diseases / Q000378:metabolism; D008748:Methylcholanthrene / Q000494:pharmacology; D010634:Phenobarbital / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D014801:Vitamin A / Q000378:metabolism*
D014801:Vitamin A; D008748:Methylcholanthrene; D010634:Phenobarbital