Vitamin E and the inhibition of platelet lipoxygenase.

Lipoxygenase was assayed by the formation of hydroxy-eicosatetraenoic acid (HETE) from arachidonic acid in human and rabbit washed platelets. Platelets from vitamin E-supplemented rabbits had much less lipoxygenase activity than platelets from either vitamin E-deficient or normal rabbits. Human and rabbit platelets preincubated with vitamin E had lowered lipoxygenase activity. These data show that vitamin E inhibits platelet lipoxygenase. Vitamin E and vitamin E acetate, in vitro, were equally effective inhibitors of lipoxygenase. Tween 20, in vitro, was a highly effective inihbitor of lipoxygenase. These data show that vitamin E functions, in vitro, as a surfactant in the inhibition of platelet lipoxygenase.