Competitive inhibitions in the metabolism of polyunsaturated fatty acids studied via the composition of phospholipids, triglycerides and cholesteryl esters of rat tissues

Abstract

Abstract Male rats which had been kept on fat‐free diet and which were deficient in essential fatty acids were divided into ten groups. All ten groups received 0.8% of calories of linolenate, and nine received one of three levels of either linoleate, े‐linolenate or arachidonate for a period of six days. The rats were sacrificed, the livers, kidneys and testes were extracted, and the phospholipids, triglycerides and cholesteryl esters were separated by thin‐layer chromatography. The fatty acid composition of each was determined by gas‐liquid chromatography. The inhibition of the metabolism of linolenic acid by linoleate, े‐linolenate and arachidonate was evidenced in all three lipid classes and in all tissues. The activities in suppressing linolenate metabolism were in the order 20:4 >18:3 >18:2.