Factors which can influence beta-oxidation by peroxisomes isolated from livers of clofibrate treated rats. Some properties of peroxisomal fractions isolated in a self-generated Percoll gradient by vertical rotor centrifugation.
1. Oxidation of radioactivity labeled acyl-CoA esters by apparently intact peroxisomes, isolated from rats treated with clofibrate, was stimulated by about 100% by added oxaloacetate. Added pyruvate gave much smaller stimulation. This stimulation is proposed to be due to re-oxidation of NADH generated during peroxisomal beta-oxidation of acyl-CoA esters. 2. Additions of these alpha-ketoacids, and of CoA, were found to influence extent of peroxisomal beta-oxidation of [U-14C]palmitoyl-CoA. Various concentrations of added CoA was markedly less inhibitory to oxidation of [14-14C]erucoyl-CoA and [10-14C]elaidoyl-CoA, as compared to [U-14C]palmitoyl-CoA. 3. Added NADP+, at concentrations higher than 0.5 mM, added NADPH and NADH were inhibitory to peroxisomal beta-oxidation of [U-14C]palmitoyl-CoA. Significant inhibition was found at concentrations which were too high for this to be of significance in vivo.
D000818:Animals; D002499:Centrifugation, Density Gradient / Q000379:methods; D055598:Chemical Phenomena; D002621:Chemistry; D002994:Clofibrate / Q000494:pharmacology*; D003065:Coenzyme A / Q000494:pharmacology; D008099:Liver / Q000378:metabolism*; D008297:Male; D008830:Microbodies / Q000187:drug effects / Q000378:metabolism*; D009243:NAD / Q000378:metabolism; D009940:Organoids / Q000378:metabolism*; D010084:Oxidation-Reduction / Q000187:drug effects*; D051381:Rats; D011919:Rats, Inbred Strains
D009243:NAD; D002994:Clofibrate; D003065:Coenzyme A