INTRODUCTION: In vivo, initial platelet activation is likely caused by platelet contacts with collagen in the subendothelium or from the small amounts of @entity556 formed by the tissue factor/factor VIIa complex. Our aim was to study the coagulative role of @entity857 released by the platelets after activation with strong stimuli such as collagen and/or @entity556 , and the relative importance of the platelet @entity857 receptors @entity15094 and @entity3075 . MATERIALS AND METHODS: We used 10 Hz free oscillation rheometry to measure clotting time, clot elasticity and fibrinolysis resistance of non-anticoagulated whole blood. The platelets were activated with a collagen-related peptide (CRP), with the @entity8781 @entity556 receptor activating peptide TRAP-6 or by @entity556 , the latter generated by small amounts of thromboplastin. To inhibit the platelet @entity857 receptors, we used the @entity15094 antagonist @entity24001 and the @entity3075 antagonist @entity37502 . RESULTS: Both antagonists significantly retarded the clotting induced by CRP. The effects were most pronounced with @entity37502 . For TRAP-6, the same trend was seen, but the retardation was only significant with @entity37502 . Clotting induced by small amounts of thromboplastin was not affected by any @entity857 -receptor antagonist. Addition of both antagonists did not change the results as compared to samples with @entity37502 alone. Nor did the antagonists, one at a time or in concert, effect fibrinolysis or the elastic properties of the clot. CONCLUSION: We conclude that @entity857 -receptor inhibition prolongs the clotting time for whole blood activated by CRP, but that it does not affect the properties of the subsequently formed coagulum.

Effects of inhibition of XXXX and @entity3075 on whole blood clotting, coagulum elasticity and fibrinolysis resistance studied with free oscillation rheometry.

@entity24001 :: ('MESH:C111914', 'Chemical') :: ['MRS2179'] @entity556 :: ('2147', 'Gene') :: ['thrombin'] @entity37502 :: ('MESH:C117446', 'Chemical') :: ['AR-C69931MX'] @entity857 :: ('MESH:D000244', 'Chemical') :: ['ADP'] @entity3075 :: ('64805', 'Gene') :: ['P2Y(12)'] @entity15094 :: ('5028', 'Gene') :: ['P2Y(1)'] @entity8781 :: ('2149', 'Gene') :: ['PAR1']
@entity15094 :: (5028,Gene) :: ['P2Y(1)']
