The effect of vitamin E deficiency on some platelet membrane properties.

The effects of alpha-tocopherol (vitamin E) deficiency on membrane properties of platelets were studied to determine if vitamin E has a measureable stabilizing role in biological membranes. Three groups of rats and three of mice were studied: two groups consisted of Fisher strain rats and one of Sprague-Dawley rats fed a Draper corn oil diet with and without high levels of supplementary vitamin E. The mice were two groups of BALB/c animals maintained on an 8% hydrogenated coconut oil diet, and one group of CBA/J mice on an 8% lard diet, in each case either deficient in or supplemented with vitamin E. The relative content of fatty acids obtained from both rat platelets and erythrocytes was unchanged by vitamin E deficiency. Depletion of vitamin E had no effect on the degree of fluorescence polarization of 1,6-diphenyl-1,3,5,-hexatriene-labeled rat platelets. No changes in hematocrit values were seen in any of the studies. The platelet count of only the vitamin E-deficient Sprague-Dawley rats was elevated with respect to vitamin E-supplemented counterparts; the others remained constant. Platelet reactivities, as measured by ADP-and thrombin-induced platelet aggregation and by the thrombin-induced changes in platelet transmembrane potential, were unaffected by vitamin E deficiency in all three groups of rats. Our results indicate that a membrane stabilizing effect of vitamin E on rat platelet or erythrocyte membrane fatty acids or on platelet response to external stimuli could not be demonstrated, nor was elevation in platelet count a general phenomenon associated with vitamin E deficiency.-Whitin, J. C., R. K. Gordon, L. M. Corwin, and E. R. Simons. The effect of vitamin E deficiency on some platelet membrane properties.