Comparison of cytochrome P-450- and peroxidase-mediated activations of carcinogenic azo dyes and N-nitrosamines.
Carcinogenic azo dyes (dimethylaminoazobenzene, Sudan I) and N-nitrosamines (N-nitrosomethylaniline, N-nitrosomethylbenzylamine) are oxidized by cytochrome P-450 isoenzymes and peroxidase yielding metabolites which in vitro bind to DNA and transfer RNA (tRNA). The parallelism and differences in oxidative reactions are described. Peroxidase is more effective than P-450 in activating reactions of some carcinogens studied. The presence of either of these enzymes is supposed to be responsible for the organ and/or cell type specific effects of the carcinogens studied.
Stiborová
M
M
Department of Biochemistry, Faculty of Natural Sciences, Charles University, Prague, Czechoslovakia.
Frei
E
E
Schmeiser
H H
HH
D000818:Animals; D001391:Azo Compounds / Q000493:pharmacokinetics*; D001711:Biotransformation; D002273:Carcinogens / Q000493:pharmacokinetics*; D004396:Coloring Agents / Q000493:pharmacokinetics; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D066298:In Vitro Techniques; D007527:Isoenzymes / Q000378:metabolism; D008297:Male; D008862:Microsomes, Liver / Q000201:enzymology; D009602:Nitrosamines / Q000493:pharmacokinetics*; D009928:Organ Specificity; D010084:Oxidation-Reduction; D010544:Peroxidases / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
D001391:Azo Compounds; D002273:Carcinogens; D004396:Coloring Agents; D007527:Isoenzymes; D009602:Nitrosamines; D003577:Cytochrome P-450 Enzyme System; D010544:Peroxidases