Docosahexaenoic acid (DHA) was isolated from cellular membranes at the sn-2 position of phospholipids (PLs). Using conformation modeling computer software, data were obtained indicating DHA in PLs to possibly be tightly and regularly packed in the acyl chain array in cellular membranes under certain conditions.
PLs containing DHA had stereospecific conformations, which may possibly be the reason for the important physiological functions of this lipid. PLs containing DHA express difference induction and inhibited 5-lipoxygenase and lecithin-cholesterol acyltransferase activity. They were found essential to integrated brain functions such as learning ability and the inducement of paradoxical sleep.