Ethanol feeding to rats reversibly decreases hepatic carnitine palmitoyltransferase activity and increases enzyme sensitivity to malonyl-CoA.
The effects of prolonged ethanol feeding on both carnitine palmitoyltransferase I activity and enzyme sensitivity to inhibition by malonyl-CoA were studied in rat liver, heart, skeletal muscle and kidney cortex mitochondria. Heart and skeletal muscle enzymes showed the highest specific activity and sensitivity to malonyl-CoA. Carnitine palmitoyltransferase I in extrahepatic tissues showed no changes on ethanol feeding. Only the liver enzyme activity was altered after long term ethanol administration, by suffering a progressive decrease in activity and a parallel increase in sensitivity to malonyl-CoA. These alterations reversed after 10 days of ethanol withdrawal. These results are discussed in relation to the control of carnitine palmitoyltransferase I and the effects of ethanol on fatty acid metabolism.
Department of Biochemistry, Faculty of Chemistry, Universidad Complutense, Madrid, Spain.
M
M
Guzmán
J
J
Castro
A
A
Maquedano
D000214:Acyl Coenzyme A / Q000494:pharmacology*; D000217:Acyltransferases / Q000037:antagonists & inhibitors*; D000818:Animals; D002334:Carnitine O-Palmitoyltransferase / Q000037:antagonists & inhibitors*; D000431:Ethanol / Q000494:pharmacology*; D005227:Fatty Acids / Q000378:metabolism; D008099:Liver / Q000201:enzymology*; D008297:Male; D008316:Malonyl Coenzyme A / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D014280:Triglycerides / Q000378:metabolism
D000214:Acyl Coenzyme A; D005227:Fatty Acids; D014280:Triglycerides; D000431:Ethanol; D008316:Malonyl Coenzyme A; D000217:Acyltransferases; D002334:Carnitine O-Palmitoyltransferase