Preliminary observations on abnormalities of membrane structure and function in essential hypertension.

Abstract

To test the hypothesis that structural abnormalities exist in the cell membrane in persons with essential hypertension and that these abnormalities affect membrane-related cellular functions, we examined several membrane-dependent phenomena and membrane lipid composition in the blood cells of subjects with essential hypertension. We analyzed platelet aggregability, membrane fluidity, membrane fatty acid composition, and erythrocyte deformability in four normolipidemic subjects with untreated essential hypertension and in five age-matched normotensive controls. As compared with the controls, the subjects with essential hypertension had platelets that aggregated at lower concentrations of adenosine 5'-diphosphate, platelet membranes that were less fluid, and erythrocytes that were more deformable. Lipid analysis of the membranes of platelets from the two study groups showed that although the cholesterol content was identical, the membranes from the essential hypertension group contained significantly less linoleic acid (18:2) than did those from the normotensive controls. Given the known effects of cis-unsaturated fatty acyl composition on membrane fluidity and membrane-related cellular functions, these data suggest that one factor contributing to essential hypertension is an inherent structural membrane abnormality that alters the physical and functional properties of the cell membrane.