[Effect of prethrombin I and prostaglandin E2 on thrombin-stimulated aggregation of rat platelets].
Effect of inactive precursor of alpha-thrombin--prethrombin (Pre-I) and prostaglandin (PGE2) on aggregation of washed rat platelets induced by alpha-thrombin was studied. Pre-I inhibited dose-dependently the alpha-thrombin-induced platelet aggregation. K1 values for Pre-I of high and low affinity binding sites were equal to 0.9.10(-8) M and 0.56.10(-6) M, respectively. PGE2 inhibited the alpha-thrombin-induced aggregation after simultaneous addition and within 5 and 15 min of incubation with PGE2. Preincubation of platelets with alpha-thrombin within 15 min prevented the PGE2-induced aggregation but preincubation of platelets with Pre-I within 15 min did not influence the platelet aggregation, induced by PGE2.
D000818:Animals; D015232:Dinoprostone; D004792:Enzyme Precursors / Q000494:pharmacology / Q000502:physiology*; D066298:In Vitro Techniques; D007700:Kinetics; D008297:Male; D010974:Platelet Aggregation; D011458:Prostaglandins E / Q000494:pharmacology / Q000502:physiology*; D011516:Prothrombin / Q000494:pharmacology / Q000502:physiology*; D051381:Rats; D013917:Thrombin / Q000494:pharmacology / Q000502:physiology*
D004792:Enzyme Precursors; D011458:Prostaglandins E; D011516:Prothrombin; C012007:prethrombins; D013917:Thrombin; D015232:Dinoprostone
Vliianie pretrombina I i prostaglandina E2 na stimuliruemuiu trombinom agregatsiiu trombotsitov krys.