【作者】 庞懿；

【导师】 薛全福； 许澍淮；

【作者基本信息】 中国协和医科大学 ， 病理生理学， 1998， 博士

【摘要】 在动脉粥样硬化时，血小板和血管间的相互作用在冠心病事件中起重要作用。血小板激活后释放多种血管活性物质，促进血栓形成，并引起血管收缩反应。其中，血小板释放的5-HT在血小板聚集和血管痉挛中发挥重要作用。当血小板在受损的血管表面粘附、聚集和激活后，可释放大量的5-HT，后者通过刺激血小板表面的5-HT_2A受体，使血小板进一步激活，从而形成恶性循环，诱发血栓形成，5-HT_2A受体拮抗剂有明显抑制血栓形成的作用。生理状态下5-HT是血小板弱的激活剂。它引起的血小板聚集是可逆的，因此冠心病时5-HT引起的血小板聚集并发展成血栓与此时血小板对5-HT的反应性增高有关。本室以前的部分工作表明冠心病患者存在血小板对5-HT的高反应，蛇毒抗栓酶（SVATE）可抑制这种高反应性，并设想血小板对5-HT的高反应性可能与血小板上5-HT_2A受体的变化有关，但到目前为止，尚未见这方面的报道。5-HT在冠心病中另一重要作用是它能诱发冠脉痉挛。向冠心病患者冠脉内注入不引起正常人冠脉收缩的低剂量的5-HT可诱发典型的冠脉痉挛和心肌缺血。在粥样硬化的离体动脉（主动脉，颈动脉，冠状动脉）上，5-HT引起的血管收缩反应要比正常动脉的收缩反应强得多。这种动脉血管对5-HT的高反应性与动脉粥样硬化有密切的关系，而且显然是由于动脉血管本身更多还原

【Abstract】 Interaction between platelets and arterial wall induced by pathogenetic factors plays an important role in the pathogenesis of coronary heart disease（CHD）. A lot of vasoactive agents released from aggregated platelet contribute to thrombosis and vascular contraction, which will lead to myocardial ischemia and infarction. Studies implicated that 5-HT, when released from aggregated platelets, is extremly important in inducing platelet aggregation and coronary artery spasm. Platelet aggregated at any site of injuried artery wall, will release more 5-HT, which further in turn stimulate 5-HT_2A receptor located in platelet membrane. As a result, more platelet aggregates and a vicious cycle is formed. In physiological state, 5-HT is just a weak inducer of platelet aggregation, and this aggregation is reversible. However, the circumstance is quite different in CHD, in which platelet become more sensitive to 5-HT compared with normal. Our previous studies showed that platelet aggregation induced by 5-HT in patients with acute mycardial infarction was significantly higher than that of control, and snake venom anti-thrombosis enzyme（SVATE） could inhibit the platelet hyperreactivity incuced by 5-HT. No data were shown whether platelet 5-HT_2A receptor changed and contributed to platelet hyperreactivity in those patients. Another important role of 5-HT in CHD is that 5-HT can induce coronary arterial spasm. In patients with angina, intracoronary infusion of 5-HT with concentration only leads to normal coronary arterial dilation could induce更多还原