Halushka P V, Kochel P J, Mais D E
Br J Pharmacol. 1987 May;91(1):223-7. doi: 10.1111/j.1476-5381.1987.tb09002.x.
The competition of [125I]-9, 11 dimethylmethano-11, 12 methano-16-(3-iodo-4-hydroxyphenyl)-13, 14-dihydro-13-aza 15 alpha beta-omega-tetranor-thromboxane A2 ([125I]-PTA-OH), a thromboxane A2/prostaglandin H2 receptor antagonist, with a series of thromboxane A2/prostaglandin H2 (TXA2/PGH2) mimetics for binding to the putative TXA2/PGH2 receptor in washed human platelets was studied. The rank order potency for the series of mimetics to compete with [125I]-PTA-OH for binding was compared with their rank order potency for induction of platelet aggregation. The rank order potency for the mimetics to compete with [125I]-PTA-OH for binding was ONO-11113 greater than SQ-26655 greater than U44069 greater than U46619 = 9, 11-azo PGH2 greater than MB28767. This rank order potency was highly correlated with their rank order potency for inducing platelet aggregation (r = 0.992). Changes in the intra or extracellular concentrations of Na+ did not have a significant effect on the competition between U46619 and [125I]-PTA-OH for binding to the putative receptor. In summary, it appears that these TXA2/PGH2 mimetics activate human platelets through the putative TXA2/PGH2 receptor.
研究了血栓素A2/前列腺素H2受体拮抗剂[125I]-9,11-二甲基甲撑-11,12-甲撑-16-(3-碘-4-羟基苯基)-13,14-二氢-13-氮杂-15αβ-ω-四降血栓素A2([125I]-PTA-OH)与一系列血栓素A2/前列腺素H2(TXA2/PGH2)模拟物在洗涤过的人血小板中与假定的TXA2/PGH2受体结合的竞争情况。将该系列模拟物与[125I]-PTA-OH竞争结合的效价顺序与其诱导血小板聚集的效价顺序进行了比较。模拟物与[125I]-PTA-OH竞争结合的效价顺序为:ONO-11113大于SQ-26655大于U44069大于U46619 = 9,11-偶氮PGH2大于MB28767。该效价顺序与其诱导血小板聚集的效价顺序高度相关(r = 0.992)。细胞内或细胞外Na+浓度的变化对U46619与[125I]-PTA-OH竞争结合假定受体没有显著影响。总之,这些TXA2/PGH2模拟物似乎通过假定的TXA2/PGH2受体激活人血小板。