Effect of n-octylamine on the reduction of mammalian hepatic microsomal cytochrome b5.
1. In a preceding paper evidence was presented for the endogenous reduction of NAD(P)+ by mammalian hepatic microsomes and the concomitant reduction of cytochrome b5. The experiments reported here demonstrate that low concentrations of n-octylamine, in the presence of limiting quantities of NAD+, cause an increased level of cytochrome b5 reduction by mouse hepatic microsomes and also delays its reoxidation. 2. These effects are both NAD+ and n-octylamine dependent and appear to be due to an activation of the microsomal enzyme causing endogenous reduction of NAD(P)+ and also, in part, to inhibition of the autooxidation of reduced cytochrome b5. 3. Protection from the inhibitory action of sulfhydryl reagents on NADH-cytochrome b5 reductase was also observed in the presence of n-octylamine. 4. The results suggest that the enzyme(s) involved in the endogenous reduction of NAD(P)+ is not the microsomal alcohol dehydrogenase.
D000588:Amines / Q000378:metabolism / Q000494:pharmacology*; D000818:Animals; D003579:Cytochrome Reductases / Q000378:metabolism*; D042966:Cytochrome-B(5) Reductase; D051379:Mice; D008862:Microsomes, Liver / Q000201:enzymology*; D009249:NADP / Q000378:metabolism; D009536:Niacinamide / Q000494:pharmacology; D010084:Oxidation-Reduction / Q000187:drug effects
D000588:Amines; D009536:Niacinamide; D009249:NADP; D003579:Cytochrome Reductases; D042966:Cytochrome-B(5) Reductase; C008699:octylamine