Extrahepatic microsomal metabolism of N-nitrosodi-n-butylamine in rats.
The omega- and omega-1-hydroxylation of N-nitrosodi-n-butylamine (NDBA) has been studied in microsomes from rat liver, lung, intestine and kidney. Both reactions followed at least two enzyme kinetics with low (2-10 microM) and high (1 mM) Km values. Whereas omega-1-hydroxylation was the predominant pathway in liver, omega-hydroxylation was more important in extrahepatic tissues. First-pass metabolism of NDBA in lungs and intestinal mucosa may be of importance in the development of urinary bladder tumours in rats.
Richter
E
E
Walther Straub-Institut für Pharmakologie und Toxikologie, Ludwig-Maximilians-Universität München, Federal Republic of Germany.
Schulze
J
J
Zwickenpflug
W
W
D000818:Animals; D005260:Female; D007421:Intestine, Small / Q000648:ultrastructure; D007668:Kidney / Q000648:ultrastructure; D007700:Kinetics; D008168:Lung / Q000648:ultrastructure; D008861:Microsomes / Q000378:metabolism*; D008862:Microsomes, Liver / Q000378:metabolism; D009602:Nitrosamines / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
D009602:Nitrosamines; C012279:dibutylnitrosamine