title: Activation of acetaminophen oxidation in rat liver microsomes by caffeine.
abstract: Addition of caffeine in vitro stimulated the oxidative metabolism of acetaminophen by rat liver microsomes, resulting in increased formation of acetaminophen-glutathione (GSH) conjugates and increased covalent binding of acetaminophen to microsomal protein. This metabolic enhancement by caffeine was most prominent using liver microsomes from phenobarbital (PB)-treated rats. Liver microsomes obtained from rats treated with ethanol-oxidized acetaminophen at much faster rates than microsomes from control, PB-treated or 3-methylcholanthrene (3-MC)-treated animals. The stimulatory effect of caffeine was, however, minimal in liver microsomes obtained from ethanol-treated rats.
mesh_terms: D000082:Acetaminophen / Q000378:metabolism*; D000096:Acetone / Q000494:pharmacology; D000818:Animals; D001711:Biotransformation; D002110:Caffeine / Q000494:pharmacology*; D003577:Cytochrome P-450 Enzyme System / Q000032:analysis; D000431:Ethanol / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology; D066298:In Vitro Techniques; D008099:Liver / Q000187:drug effects; D008297:Male; D008748:Methylcholanthrene / Q000494:pharmacology; D008862:Microsomes, Liver / Q000378:metabolism*; D010084:Oxidation-Reduction; D010634:Phenobarbital / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D005419:Flavonoids; D000096:Acetone; D000082:Acetaminophen; D002110:Caffeine; D000431:Ethanol; D008748:Methylcholanthrene; D003577:Cytochrome P-450 Enzyme System; D010634:Phenobarbital