The utilization of whole-body autoradiography and allied tracer techniques in distribution and biotransformation studies of N-nitrosamines.
The tissue-disposition of various N-nitrosamines has been examined by whole-body autoradiography and allied tracer techniques in a series of studies at our department. Tracing of N-nitrosamine-metabolizing tissues was a major purpose of the studies. The data obtained provide evidence that the in vivo localization of N-nitrosamine metabolites in various tissues is almost invariably due to local metabolism in the same tissues and that the tumourigenesis by N-nitrosamines is to a considerable extent correlated with this metabolism. The epithelial linings of the upper digestive tract and respiratory pathways were usually very active in N-nitrosamine metabolism, and these tissues also were prevalent sites for N-nitrosamine-carcinogenesis. The presence of cytochrome P-450-activity has been shown in these structures and may normally play a role in defending the body against unrestrained uptake of xenobiotics. However, noxious effects may instead be induced for chemicals bioactivated by cytochrome P-450-dependent reactions, such as N-nitrosamines.
Tjälve
H
H
D000818:Animals; D001345:Autoradiography; D001711:Biotransformation; D002143:Callitrichinae; D055598:Chemical Phenomena; D002621:Chemistry; D006224:Cricetinae; D008647:Mesocricetus; D051379:Mice; D008810:Mice, Inbred C57BL; D009602:Nitrosamines / Q000493:pharmacokinetics*; D051381:Rats; D011919:Rats, Inbred Strains; D013552:Swine; D013556:Swine, Miniature; D014018:Tissue Distribution
D009602:Nitrosamines