Uptake and Metabolism of ¹⁴C-Labeled Oleic Acid by Atherosclerotic Lesions in Rabbit Aorta

A Biochemical And Radioautographic Study

¹ Department of Physiology, University of Melbourne, Victoria 3052, Australia

The uptake of ¹⁴C-labeled oleic acid and its incorporation into combined lipids by aortic intimas from normal and cholesterol-fed rabbits has been investigated in vitro. More than five times as much oleic acid was taken up by the atherosclerotic intima as by the normal intima. About twice as much oleic acid was incorporated into phospholipid, and twenty times as much into cholesterol ester by the atherosclerotic intima as by the normal. Lecithin was the major phospholipid synthesized from oleic acid in both normal and atherosclerotic intimas.

Radioautographs of the atherosclerotic vessels show that the ¹⁴C-labeled oleic acid and its metabolic derivatives, principally phospholipid and cholesterol ester, were localized in sudanophilic cells in the intima in both early and advanced lesions. It is concluded that intimal foam cells are primarily responsible for the lipid synthesis that occurs in the atherosclerotic lesion.

Accepted on October 14, 1968