title: N,N-dibutylnitrosamine metabolism by rat liver S9 fraction and oxidation by chemical model systems.
abstract: Oxidative in vitro metabolism of N,N-dibutylnitrosamine (DBN) by 9000g supernatant fraction (S9 fraction) prepared from rat liver and oxidation of DBN by chemical model systems (Udenfriend and Fenton) were investigated. The products retaining the N-nitroso group of DBN were analyzed by gas-liquid chromatography. Incubation of DBN with the S9 fraction gave hydroxy derivatives of DBN at the omega, omega-1, and omega-2 positions, while the chemical reaction of DBN in the Udenfriend and the Fenton model systems afforded compounds with an oxo group at the same positions. In all cases, omega-1 oxidation was predominant, followed by omega and then by omega-2 oxidations, while omega and omega-1 oxidations were the principal metabolic pathways of DBN in vivo in the rat. The differences in the oxidative transformation of DBN among in vitro enzymatic, non-enzymatic and in vivo systems are discussed.
mesh_terms: D000818:Animals; D001711:Biotransformation; D002273:Carcinogens / Q000378:metabolism*; D002849:Chromatography, Gas; D066298:In Vitro Techniques; D008099:Liver / Q000378:metabolism*; D008297:Male; D009152:Mutagenicity Tests; D009153:Mutagens; D009602:Nitrosamines / Q000378:metabolism*; D010084:Oxidation-Reduction; D010634:Phenobarbital / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D012486:Salmonella typhimurium / Q000187:drug effects
chemical_list: D002273:Carcinogens; D009153:Mutagens; D009602:Nitrosamines; C012279:dibutylnitrosamine; D010634:Phenobarbital