Prostaglandin H synthase oxidation of benzidine and o-dianisidine: reduction and conjugation of activated amines by thiols.
Prostaglandin H synthase oxidized the carcinogens benzidine and o-dianisidine to their respective quinonediimines. Analysis of the reaction media by u.v./visible spectroscopy and liquid chromatography with electrochemical and radiochemical detection revealed that these quinonediimines can be both conjugated and reduced by glutathione, cysteine and N-acetylcysteine. Analysis of the purified conjugate formed between synthetic benzidinediimine and glutathione by proton magnetic resonance spectroscopy demonstrated the product to be 3-(glutathion-S-yl)-benzidine. This metabolite was also formed during peroxidation of benzidine by prostaglandin H synthase in the presence of excess glutathione. These conjugates may be useful markers of peroxidatic activation of aromatic amines in vivo.
D000588:Amines / Q000378:metabolism*; D001560:Benzidines / Q000378:metabolism*; D003962:Dianisidine / Q000378:metabolism*; D005978:Glutathione / Q000378:metabolism; D066298:In Vitro Techniques; D009682:Magnetic Resonance Spectroscopy; D010084:Oxidation-Reduction; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism*; D013056:Spectrophotometry, Ultraviolet; D013438:Sulfhydryl Compounds / Q000494:pharmacology*
D000588:Amines; D001560:Benzidines; D013438:Sulfhydryl Compounds; C029876:benzidine; D011451:Prostaglandin-Endoperoxide Synthases; D005978:Glutathione; D003962:Dianisidine