title: Role of different cytochrome P-450 isozymes in the demethylation of various substrates.
abstract: Phenobarbital treatment of rats enhanced 2-fold the hepatic aninopyrine (AP) and dimethylhydrazine (DMH) demethylation but not that of N-nitrosodimethylamine (NDMA). Pyrazole enhanced the demethylation rate of DMH and NDMA but not that of AP. The in vitro effects of metyrapone and SKF-525A on the demethylation rate of various substrates were dependent on the substrate and treatment of rats. The data suggest that the demethylation of various substrates might be catalyzed by different cytochrome P-450 isozymes.
mesh_terms: D019813:1,2-Dimethylhydrazine; D000632:Aminopyrine / Q000378:metabolism; D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D004127:Dimethylhydrazines / Q000378:metabolism; D004128:Dimethylnitrosamine / Q000378:metabolism; D066298:In Vitro Techniques; D007527:Isoenzymes / Q000378:metabolism*; D008297:Male; D008797:Metyrapone / Q000494:pharmacology; D008862:Microsomes, Liver / Q000378:metabolism; D010089:Oxidoreductases, N-Demethylating / Q000378:metabolism; D011335:Proadifen / Q000494:pharmacology; D051381:Rats; D013379:Substrate Specificity
chemical_list: D004127:Dimethylhydrazines; D007527:Isoenzymes; D000632:Aminopyrine; D003577:Cytochrome P-450 Enzyme System; D011335:Proadifen; D010089:Oxidoreductases, N-Demethylating; D019813:1,2-Dimethylhydrazine; D004128:Dimethylnitrosamine; D008797:Metyrapone