title: Increased response of cytochrome P-450 dependent biotransformation reactions in rat liver to repeated administration of inducers.
abstract: A single intraperitoneal administration of 3-methylcholanthrene (3MC) or beta-naphthoflavone (BNF) increased aryl hydrocarbon hydroxylase (AHH) and 7-ethoxyresorufin 0-deethylase (EROD) activities. Following a second administration of both inducers 3-4 weeks later, the extent of induction was considerably greater. Such a "booster"-phenomenon was also observed with different cytochrome P-450 (P-450)-dependent N-demethylation reactions after repeated phenobarbital (PB) administrations. Again the P-450 content was higher than after a single PB administration.
mesh_terms: D000818:Animals; D001189:Aryl Hydrocarbon Hydroxylases / Q000096:biosynthesis*; D001571:Benzoflavones / Q000008:administration & dosage / Q000494:pharmacology*; D001711:Biotransformation / Q000187:drug effects*; D019363:Cytochrome P-450 CYP1A1; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D004790:Enzyme Induction / Q000187:drug effects; D005419:Flavonoids / Q000494:pharmacology*; D008099:Liver / Q000187:drug effects / Q000201:enzymology; D008297:Male; D008748:Methylcholanthrene / Q000008:administration & dosage / Q000494:pharmacology*; D010088:Oxidoreductases / Q000096:biosynthesis*; D010634:Phenobarbital / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D019324:beta-Naphthoflavone
chemical_list: D001571:Benzoflavones; D005419:Flavonoids; D008748:Methylcholanthrene; D019324:beta-Naphthoflavone; D003577:Cytochrome P-450 Enzyme System; D010088:Oxidoreductases; D001189:Aryl Hydrocarbon Hydroxylases; D019363:Cytochrome P-450 CYP1A1; D010634:Phenobarbital