Inhibition of the hormone-sensitive lipase in adipose tissue by long-chain fatty acyl coenzyme A.
The effects of free fatty acids and fatty acyl esters of coenzyme A and carnitine on the activity of a hormone-sensitive lipase preparation made from pigeon adipose tissue were determined. Oleic acid (100 microM) resulted in a 40% inhibition of lipase activity. A more potent inhibition of lipase activity was seen with long-chain fatty acyl CoA compounds. The concentration required for half-maximal inhibition with oleoyl CoA and palmitoyl CoA was 25-40 microM, whereas palmitoyl carnitine stimulated lipase activity. Activated lipase preparations (preincubated with Mg2+, ATP, cyclic AMP and protein kinase) were 4-6 times more sensitive to inhibition by oleoyl CoA than were nonactivated preparations. An increase in cellular levels of fatty acyl coenzyme A could, therefore, contribute to the feedback inhibition of lipolysis in adipose tissue.
D000214:Acyl Coenzyme A / Q000494:pharmacology*; D000255:Adenosine Triphosphate / Q000494:pharmacology; D000273:Adipose Tissue / Q000201:enzymology*; D000818:Animals; D002331:Carnitine / Q000494:pharmacology; D010856:Columbidae; D000242:Cyclic AMP / Q000494:pharmacology; D005230:Fatty Acids, Nonesterified / Q000494:pharmacology*; D066298:In Vitro Techniques; D019301:Oleic Acid; D009829:Oleic Acids / Q000494:pharmacology; D011494:Protein Kinases / Q000378:metabolism; D002787:Sterol Esterase / Q000037:antagonists & inhibitors*
D000214:Acyl Coenzyme A; D005230:Fatty Acids, Nonesterified; D009829:Oleic Acids; D019301:Oleic Acid; D000255:Adenosine Triphosphate; D000242:Cyclic AMP; D011494:Protein Kinases; D002787:Sterol Esterase; D002331:Carnitine