Stereospecific Distribution of Fatty Acids in Human Plasma Triglycerides

Because of a biological difference between both primary hydroxylgroups of glycerol there are three distinct hydroxylgroups esterified with fatty acids in triglycerides. The distribution of fatty acids in the three distinct positions of triglycerides can be investigated by a combination of partial hydrolysis of triglycerides by pancreatic lipase, phosphorylation of the diglycerides formed and the stereospecific action of phospholipase A on phosphatides. Plasma triglycerides from normal and hyperlipemic humans are analysed. Human plasma triglycerides are highly asymmetric. The 1-position contains more than twice as much palmitic acid as the 3-position. Statistically significant differences are found between normal and hyperlipemic humans for palmitic and linoleic acid at the 2-position, and for oleic and linoleic acid at the 3-position.