Phospholipid content and fatty acid composition of human heart

Phospholipid content and fatty acid composition of human heart were determined on 36 biopsy specimens collected during open heart surgery. The main phospholipid classes, phosphatidylcholine (PC), phosphatidylethanolamine (PE), diphosphatidylglycerol (DPG), and sphingomyelin (SPH) were separated by HPLC, quantified, and converted to fatty acid methyl esters which were chromatographed on capillary GLC columns. Sex and age (mainly 40-70) of patients had no significant influence on the relative distribution of phospholipid classes and only a slight effect on fatty acid composition. Incorporation of trans 18:1 in phospholipid classes was low. cis and trans octadecenoic isomers seemed to be selectively incorporated, the delta 9 and delta 11 cis or trans isomers being predominant. Human and rat data were compared, and some species differences were noticed. In human PC, palmitic acid is higher and stearic acid much lower than in rat PC. Saturated dimethyl acetals (16:0 and 18:0) in PC and PE were greater for humans. Incorporation of 20:4 n-6 in human PE is higher than in rat PE.