The homogeneity of rat liver microsomal cytochrome P-448 activity and its role in the activation of benzo[a]pyrene to mutagens.
The O-deethylation of ethoxyresorufin and the metabolic activation of benzo[a]pyrene to mutagens were determined in hepatic microsomal preparations from control and induced animals. An excellent direct correlation (r = 0.95) has been observed between ethoxyresorufin O-deethylase and the metabolic activation of benzo[a]pyrene to mutagens when the fraction of cytochromes P-450 present as cytochrome P-448 was altered by the administration of phenobarbitone and 3-methylcholanthrene alone or in combination with 9-hydroxyellipticine. The correlation between these activities was maintained following treatment of animals with Arochlor 1254, benzo[a]pyrene, benzo[e]pyrene, 7,12-dimethylbenzo[a]anthracene,2-anthramine and 2-naphthylamine.
D000818:Animals; D001564:Benzo(a)pyrene / Q000378:metabolism*; D001711:Biotransformation; D019388:Cytochrome P-450 CYP1A2; D003580:Cytochromes / Q000378:metabolism*; D004790:Enzyme Induction; D008297:Male; D008862:Microsomes, Liver / Q000201:enzymology / Q000378:metabolism*; D006899:Mixed Function Oxygenases / Q000378:metabolism; D009152:Mutagenicity Tests; D051381:Rats; D011919:Rats, Inbred Strains
D003580:Cytochromes; D001564:Benzo(a)pyrene; D006899:Mixed Function Oxygenases; C017170:Cyp1a2 protein, rat; D019388:Cytochrome P-450 CYP1A2