title: Effect of dietary vitamin E on platelet tocopherol values and 12-lipoxygenase activity.
abstract: This study was designed to evaluate the effects of different amounts of dietary vitamin E on platelet tocopherol levels and 12-lipoxygenase activity when exogenous arachidonic acid was used as substrate. Weanling male Sprague-Dawley rats were fed diets containing 0, 50, and 5000 ppm of D-alpha-tocopherol acetate for 4 months. Platelet tocopherol was increased with increasing concentrations of dietary vitamin E; however, the conversion of exogenously added arachidonate by platelet to 12-HETE (12-hydroxyeicosatetraenoic acid) and thromboxane B2 from these three dietary groups was essentially the same. This study provides direct evidence that platelet 12-lipoxygenase activity is independent of its vitamin E content when exogenously added arachidonate was used as substrate.
mesh_terms: D000818:Animals; D001092:Arachidonate 12-Lipoxygenase / Q000097:blood*; D001091:Arachidonate Lipoxygenases / Q000097:blood*; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000097:blood; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism*; D004032:Diet; D007213:Indomethacin / Q000494:pharmacology; D007700:Kinetics; D008297:Male; D009637:Masoprocol / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D014810:Vitamin E / Q000097:blood / Q000494:pharmacology*
chemical_list: D001095:Arachidonic Acids; D014810:Vitamin E; D016718:Arachidonic Acid; D009637:Masoprocol; D001091:Arachidonate Lipoxygenases; D001092:Arachidonate 12-Lipoxygenase; D007213:Indomethacin