Fuse I, Hattori A, Mito M, Higuchi W, Yahata K, Shibata A, Aizawa Y
First Department of Internal Medicine, Niigata University School of Medicine, Japan.
Thromb Haemost. 1996 Dec;76(6):1080-5.
Five patients with mild bleeding tendencies characterized by defective thromboxane A2 (TXA2)-induced platelet aggregation are reported. The platelets of all the patients had the ability to bind exogenous TXA2. Bleeding time was markedly prolonged in one patient. In three of the five patients, synthetic TXA2 mimetic (STA2)-induced platelet responses, including IP3 formation, Ca2+ mobilization, phosphatidic acid formation and GTPase activities were selectively defective, suggesting impaired coupling between the TXA2 receptor and phospholipase C activation. However, in the remaining two patients, these responses were all within normal limits. This suggests that the defective site of this type of platelet disorder is heterogenous and that signaling mechanisms other than the TXA2 receptor-phospholipase C pathway are also involved in TXA2-induced platelet aggregation.
报告了5例以血栓素A2（TXA2）诱导的血小板聚集缺陷为特征的轻度出血倾向患者。所有患者的血小板都有结合外源性TXA2的能力。1例患者的出血时间明显延长。在5例患者中的3例，合成TXA2模拟物（STA2）诱导的血小板反应，包括肌醇三磷酸（IP3）形成、钙离子动员、磷脂酸形成和鸟苷三磷酸酶（GTPase）活性均有选择性缺陷，提示TXA2受体与磷脂酶C激活之间的偶联受损。然而，其余2例患者的这些反应均在正常范围内。这表明这类血小板疾病的缺陷部位是异质性的，并且除TXA2受体-磷脂酶C途径外的信号传导机制也参与TXA2诱导的血小板聚集。
