血小板在止血和动脉血栓形成中扮演重要角色.当血管内皮损伤暴露内皮下细胞外基质时,血小板与细胞外基质结合而被激活.在血小板激活过程中,血小板膜蛋白受体发挥着至关重要的作用.当配体与血小板膜蛋白受体结合后,产生各自的信号转导路径,使血小板发生形态变化,内容物释放,并最终形成一条由内向外的共同信号通路使血小板糖蛋白(GP)Ⅱb/Ⅲa受体激活;激活的GPⅡb/Ⅲa受体与其配体结合后诱导由外向内的信号转导,进一步使血小板形态发生变化、内容物释放,并使已黏附和聚集的血小板更稳定,从而形成血小板血栓.血小板有多条膜蛋白受体信号转导通路,这些信号通路是研究抗血小板药物作用的靶点.
Platelet plays an important role in hemostasis and thrombosis. Under vascular injury, platelets instantly adhere to the exposed extracellular matrix resulting in platelet activation. In the process of platelet activation,platelet membrane proteins play a crucial role. When ligand binds to the receptor, the ligand induces signal transduction via their respective reccptors. The various receptor-specific platelet activation signaling pathways converge into common signaling cvents that stimulate platelet shape change and granule secretion and ultimately induce the "inside-out" signtling process leading to activation of the ligand-binding function of integrin GP Ⅱ b/Ⅲa. Ligand binding to integrin GP Ⅱb/Ⅲa mediates platelet adhesion and aggregation and triggers "outside-in" signaling,resulting in platelet spreading,additional granule secretion,stabilization of platelet adhesion and aggregation, and clot retraction. These associated receptor pathways are common targets in chemotherapy drug development.