title: Some factors involved in the N-oxidation of 3-substituted pyridines by microsomal preparations in vitro.
abstract: 1. Pyridine-N-oxides have been identified as metabolites in vitro of several 3-substituted pyridines. 2. Factors affecting the metabolism of these pyridines in vitro have been studied, and conditions which give the most metabolism have been established. 3. 'Pyridine-N-oxidase' activity resides mainly in the hepatic and pulmonary microsomal fractions. 4. A species difference was evident with 'pyridine-N-oxidase' activity decreasing in the order hamster, rabbit, mouse, guinea-pig and rat. 5. A sex difference in 'pyridine-N-oxidase' activity was also established in rats and mice. 6. The appropriate kinetic factors, Km and Vmax for the N-oxidation of pyridine, 3-methylpyridine and 3-chloropyridine are reported.
mesh_terms: D000818:Animals; D006224:Cricetinae; D005260:Female; D006168:Guinea Pigs; D066298:In Vitro Techniques; D007700:Kinetics; D008168:Lung / Q000378:metabolism; D008297:Male; D008861:Microsomes / Q000378:metabolism*; D008862:Microsomes, Liver / Q000378:metabolism; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D011725:Pyridines / Q000378:metabolism*; D011817:Rabbits; D051381:Rats; D012737:Sex Factors; D013045:Species Specificity; D013347:Subcellular Fractions / Q000378:metabolism
chemical_list: D011506:Proteins; D011725:Pyridines; D010088:Oxidoreductases