Intramitochondrial factors controlling hepatic fatty acid oxidation at weaning in the rat.
Fatty acid oxidation was studied in isolated liver mitochondria of rats during the suckling-weaning transition. The oxidation rate of oleyl-CoA and palmitoylcarnitine was reduced 2.5-fold in rats weaned on a high-carbohydrate diet compared to suckling rats, when acetyl-CoA produced by beta-oxidation was directed towards ketone-body synthesis. Weaning on a high-fat diet minimized this change. Channeling of acetyl-CoA towards citrate synthesis doubled the oxidation rate of both substrates in HC-weaned rats. Thus, in addition to changes in carnitine palmitoyltransferase I activity, the beta-hydroxymethylglutaryl-CoA synthase pathway is also involved in the decreased fatty acid oxidation at weaning. This was confirmed by measurement of beta-hydroxymethylglutaryl-CoA synthase pathway activity.
D000105:Acetyl Coenzyme A / Q000378:metabolism; D000214:Acyl Coenzyme A / Q000378:metabolism; D000818:Animals; D000833:Animals, Suckling; D002334:Carnitine O-Palmitoyltransferase / Q000378:metabolism; D004040:Dietary Carbohydrates / Q000494:pharmacology; D005227:Fatty Acids / Q000378:metabolism*; D006904:Hydroxymethylglutaryl-CoA Synthase / Q000378:metabolism; D007657:Ketone Bodies / Q000096:biosynthesis; D008930:Mitochondria, Liver / Q000187:drug effects / Q000378:metabolism*; D010084:Oxidation-Reduction; D010101:Oxygen Consumption; D010171:Palmitoyl Coenzyme A / Q000378:metabolism; D010172:Palmitoylcarnitine / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D014886:Weaning
D000214:Acyl Coenzyme A; D004040:Dietary Carbohydrates; D005227:Fatty Acids; D007657:Ketone Bodies; C017585:oleoyl-coenzyme A; D010171:Palmitoyl Coenzyme A; D010172:Palmitoylcarnitine; D000105:Acetyl Coenzyme A; D002334:Carnitine O-Palmitoyltransferase; D006904:Hydroxymethylglutaryl-CoA Synthase