The conjugation of 4-nitroquinoline 1-oxide, a potent carcinogen, by mammalian glutathione transferases. 4-Nitroquinoline 1-oxide conjugation by human, rat and mouse liver cytosols, extrahepatic organs of mice and purified mouse gluthathione tranferase isoenzymes

Abstract

The conjugation of 4-nitroquinoline 1-oxide with GSH by human, rat and mouse liver cytosols, by purified mouse GSH transferases and by extrahepatic organ cytosols of male and female mice was investigated. 4-Nitroquinoline 1-oxide was as effectively conjugated by human liver cytosol as was 1-chloro-2,4-dinitrobenzene, at a substrate concentration of 0.1 mM. Mouse isoenzymes composed of Yb1 and Yf subunits exhibited high activity towards 4-nitroquinoline 1-oxide. Human, rat and mouse hepatic activities towards this substrate correlated with the hepatic isoenzyme compositions.