The role of platelets in hemostasis may be influenced by alteration of the platelet redox state-the presence of antioxidants and the formation of reactive oxygen and nitrogen species. We investigated the effects of two antioxidants, resveratrol and trolox, on platelet activation. Trolox and resveratrol inhibited aggregation of washed platelets and platelet-rich plasma activated by ADP, collagen, and thrombin receptor-activating peptide. Resveratrol was a more effective agent in reducing platelet static and dynamic adhesion in comparison with trolox. The antioxidant capacity of resveratrol was, however, the same as that of trolox. After incubation of platelets with antioxidants, the resveratrol intraplatelet concentration was about five times lower than the intracellular concentration of trolox. Although both antioxidants comparably lowered hydroxyl radical and malondialdehyde production in platelets stimulated with collagen, TxB(2) levels were decreased by resveratrol much more effectively than by trolox. Cyclooxygenase 1 was inhibited by resveratrol and not by trolox. Our data indicate that antioxidants, apart from nonspecific redox or radical-quenching mechanisms, inhibit platelet activation also by specific interaction with target proteins. The results also show the importance of studying platelet activation under conditions of real blood flow in contact with reactive surfaces, e.g., using dynamic adhesion experiments.

• MeSH
• agregace trombocytů účinky léků   fyziologie   MeSH
• antioxidancia farmakologie   MeSH
• buněčná adheze účinky léků   fyziologie   MeSH
• chromany (dihydrobenzopyrany) farmakologie   MeSH
• cyklooxygenasa 1 metabolismus   MeSH
• hemostáza účinky léků   MeSH
• kolagen farmakologie   MeSH
• kultivované buňky MeSH
• lidé MeSH
• malondialdehyd metabolismus   MeSH
• resveratrol MeSH
• stilbeny farmakologie   MeSH
• thromboxan B2 metabolismus   MeSH
• trombocyty účinky léků   fyziologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid MeSH Prohlížeč
• antioxidancia MeSH
• chromany (dihydrobenzopyrany) MeSH
• cyklooxygenasa 1 MeSH
• kolagen MeSH
• malondialdehyd MeSH
• resveratrol MeSH
• stilbeny MeSH
• thromboxan B2 MeSH