Binding of a thromboxane A2/prostaglandin H2 receptor antagonist to guinea-pig platelets.
Binding of a thromboxane A2/prostaglandin H2 receptor antagonist to guinea-pig platelets.
复制标题
血栓素 A2/前列腺素 H2 受体拮抗剂与豚鼠血小板的结合。
DOI：
10.1016/0014-2999(86)90514-5
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发表时间：
1986
影响因子：
5
通讯作者：
Garvin,M
中科院分区：
文献类型：
--
作者：
Halushka,PV;Mais,DE;Garvin,M
本文研究了血栓素A_2/前列腺素H_2受体拮抗剂[~（125）I] 9，11-二甲基亚甲基-11，12-亚甲基-16-（3-碘-4-羟基苯基）-13，14-二氢-13-氮杂-15 αβ-ω-四去甲-TXA_2（[~（125）I]PTA-OH）与洗涤的豚鼠血小板的结合。[125 I]PTA-OH以可饱和和可置换的方式与豚鼠血小板结合。[125 I]PTA-OH的Kd为14.5 ± 2 nM（n =44），Bmax为32 ± 7 fmol/107血小板或1927 ± 422个结合位点/血小板。测定了一系列13-氮杂蒎烷类TXA 2类似物拮抗TXA 2/PGH 2模拟物U46619诱导的血小板聚集和取代[125 I]PTA-OH结合位点的IC 50值。在结合试验和聚集研究中，五种拮抗剂系列的IC_（50）值高度相关（r = 0.99），比较了五种拮抗剂系列从其结合位点置换[su 125 I]PTA-OH的能力和它们诱导血小板聚集的能力。所有的激动剂完全取代配体从其结合位点，但他们的排名顺序没有相关性以及与他们的能力，以诱导聚集（r=0.37）。总的来说，这些数据与[125 I]PTA-OH结合豚鼠血小板中假定的TXA 2/PGH 2受体的观点一致。
The binding of [125I]9,11-dimethylmethano-11,12-methano-16-(3-iodo-4-hydroxyphenyl)-13,14-dihydro-13-aza-15αβ-ω-tetranor-TXA2([125I]PTA-OH), a thromboxane A2/prostaglandin H2receptor antagonist, to washed guinea-pig platelets was studied. [125I]PTA-OH bound to guinea-pig platelets in a saturable and displaceable manner. The Kdfor [125I]PTA-OH was 14.5 ± 2 nM (n =44) and the Bmaxwas 32 ± 7 fmol/107platelets or 1927 ± 422 binding sites/platelet. The IC50value for a series of 13-azapinane TXA2analogs to antagonize TXA2/PGH2mimetic U46619-induced platelet aggregation and displace [125I]PTA-OH from its binding site was determined. The IC50values for the series of five antagonists were highly correlated r = 0.99)inthebindingassaysandaggregationstudies.Theabilityofaseriesoffiveagoniststodisplace[su125I]PTA-OH from its binding site was compared to their ability to induce platelet aggregation. All the agonists completely displaced the ligand from its binding site but their rank order did not correlate well with their ability to induce aggregation (r=0.37). Collectively, the data are consistent with the notion that [125I]PTA-OH binds to a putative TXA2/PGH2receptor in guinea-pig platelets.