Palmitoyl-L-carnitine, a metabolic intermediate of the fatty acid incorporation pathway in erythrocyte membrane phospholipids

In this paper we report that palmitoyl-L-carnitine can be a metabolic intermediate of the fatty acid incorporation pathway into erythrocyte membrane phosphatidylcholine, and phosphatidhylethanolamine. Phospholipid acylation was evaluated by measuring the incorporation of radioactive [1-¹⁴C]-palmitoyl-L-carnitine in membrane erythrocyte ghost phospholipids in the presence or absence of CoA, CoA highly stimulated the incorporation of [1-¹⁴C]-palmitic acid into both the phospholipids examined, although the incorporation was also evident in the absence of added CoA. Incorporation of [1-¹⁴C]-palmitic acid into phosphatidylcholine was greater than into phosphatidylethanolamine. 2-Bromo-palmitoyl-CoA, an irreversible inhibitor of the erythrocyte carnitine palmitoyltransferase, inhibited the acylation process.