Disassociation between acidinsoluble acylcarnitines and ketogenesis following carnitine administration in vivo.
1-Carnitine was administered to fed rats and the changes in plasma beta-hydroxybutrate concentration and liver acid-insoluble acylcarnitine content were assessed. One hour following injection of carnitine in doses greater than 1 mumol/100 g of body weight there was a dose-dependent increase in liver acid-insoluble acylcarnitine content to levels comparable to those seen in fasting. These increased levels were maintained for a least 2 h following injection. During the period following carnitine administration there was no increase in ketogenesis as evidenced by plasma beta-hydroxybutyrate concentrations. Since acid-insoluble acylcarnitines represent the product of carnitine palmitoyltransferase A, the results are interpreted as contradictory to the theory that this enzyme is rate-limiting and regulatory for ketogenesis.
D000818:Animals; D002331:Carnitine / Q000031:analogs & derivatives* / Q000378:metabolism*; D006885:Hydroxybutyrates / Q000097:blood*; D007700:Kinetics; D008099:Liver / Q000378:metabolism*; D008297:Male; D051381:Rats
D006885:Hydroxybutyrates; D002331:Carnitine