title: Comparative metabolism of debrisoquine, 7-ethoxyresorufin and benzo(a)pyrene in liver microsomes from humans, and from rats treated with cytochrome P-450 inducers.
abstract: The metabolism of debrisoquine, 7-ethoxyresorufin and benzo(a)pyrene has been studied in human liver microsomes. There was a significant correlation (r = 0.70, P less than 0.05) between debrisoquine hydroxylation and 7-ethoxyresorufin 0-deethylation among various livers, and debrisoquine inhibited 7-ethoxyresorufin deethylation competitively. These results suggest that debrisoquine and 7-ethoxyresorufin may be metabolised by a common P-450 form in human liver. The effect of cytochrome P-450 inducers on the metabolism of the three substrates was also examined in rat liver. Debrisoquine hydroxylation was not enhanced by phenobarbitone, beta-naphthoflavone or isosafrole.
mesh_terms: D000818:Animals; D001564:Benzo(a)pyrene / Q000378:metabolism*; D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis*; D003647:Debrisoquin / Q000378:metabolism*; D004790:Enzyme Induction / Q000187:drug effects; D006801:Humans; D066298:In Vitro Techniques; D007546:Isoquinolines / Q000378:metabolism*; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism*; D010078:Oxazines / Q000378:metabolism*; D010634:Phenobarbital / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D007546:Isoquinolines; D010078:Oxazines; D001564:Benzo(a)pyrene; C007649:ethoxyresorufin; D003577:Cytochrome P-450 Enzyme System; D003647:Debrisoquin; D010634:Phenobarbital