OBJECTIVE To investigate the thrombolytic and antiplatelet effects of a novel plasminogen activator from the venom of Gloydius brevicaudus viper(GBV-PA)in vitro and in vivo.METHODS Thrombolytic experiments were performed in rabbit models of ear vein thrombosis and carotid artery thrombosis,and in dog model of acute cerebral infarction.Inhibition of thrombus formation was evaluated in rat inferior vena cava thrombosis model and ferric chloride-induced arterial thrombosis.In vitro,we assayed the antithrombotic effect of GBV-PA on rabbit blood clots,euglobulin lysis time(ELT)of rabbit plasma,and on ADP-induced platelet aggregation.RESULTS GBV-PA intravenous administ ration significantly reduced vascular recanalization times of rabbit ear veins thrombosis and thrombus weight of rabbit carotid artery thrombosis.The arterial recanalization rates were dose-and time-dependently improved after administration of GBV-PA in canine acute cerebral infarction model.Thrombus length and weight was significantly reduced by GBV-PA both in rat inferior vena cava and ferric chloride-induced arterial thrombosis models.Thrombus formation of blood of rabbits they were administrated with GBV-PA was also inhibited.GBV-PA radically reduced plasma ELT of rabbit′s blood clots.ADP-induced platelet aggregation was inhibited by GBV-PA in a dose-dependent manner with a half-maximal inhibitory concentration of 19.9μg·mL-1.CONCLUSION This study demonstrates that GBV-PA is a thrombolytic and antiplatelet agent.It has significant antithrombotic effects on various in vitro and in vivo experimental models of thrombosis.The mechanisms that underline its antithrombotic effects were related to GBV-PA′s capabilities of increasing fibrinolytic activities and inhibition of platelet aggregation.
目的:探讨从五步蛇毒中分离纯化凝血酶样酶的有效方法。方法:用Superdex 75、Superdex 30凝胶过滤色谱和DEAE-Sepharose Fast Flow阴离子交换色谱技术层析,SDS-PAGE分析纯度。结果:从五步蛇毒中分离纯化得到一个具有凝血活性的组分。SDS-PAGE显示为单一条带,相对分子质量约25 kDa。结论:用Superdex75、Superdex30凝胶过滤色谱和DEAE-Sepharose Fast Flow阴离子交换色谱技术可以很好分离纯化五步蛇毒中凝血酶样酶。
