蛇毒诱聚剂诱导血小板聚集机制的探讨

Researched on Mechanism of Inducing Platelet Aggregation by Platelet Aggregation Venom Reagent (PAgVR)

蛇毒诱聚剂（血小板聚集蛇毒试剂，PAgVR）是广州医学院蛇毒研究所研制成功的一种新型血小板诱聚剂．本文用比浊法探讨了PAgVR对兔血小板的作用及其影响因素．实验结果表明，PAgVR引起兔血小板聚集有赖于外源性Ca2+的存在，EDTA－Na2能完全抑制PAgVR诱导的血小板聚集，而肝素则无影响，表明PAgVR对血小板的作用与矛头蝮和响尾蛇毒不同，即不通过凝血酶而起作用；阿司匹林阻断环氧化酶和二磷酸腺苷清除剂－磷酸肌酸／磷酸肌酸激酶均不能抑制PAgVR引起的血小板聚集，而磷酸川芎嗪则能显著抑制其作用，表明PAgVR致血小板聚集作用不依赖于TXA2和血小板内源性ADP的释放，而与PAF有着某种共同的途径。

Platelet aggregation venom reagent (PAgVR) was made by Guangzhou research institute of snake venom. We reseasched the mechanism of inducing platelet aggregation by PAgVR. The experimental results showed the platelet aggregation by PAgVR was dependent upon existing Ca2+ outside the platelet. EDTA-Na2 could inhibit this aggregation,but heparin could not. Both aspirin and the ADP scavenger creatine phosphate/creatine phosphokinase (CP/CPK) failed to inhibit PAgVR -induced activation. THis experimental re sults inferred the platelet aggregation by PAgVR did not depend on TXA2-pathway and release ADP in platelet. However, Tetramethyl Pyrazine (TP),a compound isolated from Chinese herbs, prevental PAgVR-induced platelet aggregation. This action of PAgVR on washing human platelet was similar to that of platelet activating factor(PAF), suggesting PAgVR and PAF might have some pathways of platelet activation.