目的：从中国眼镜蛇毒中分高纯化出可水解纤维蛋白原的蛇毒蛋白酶，并观察其体内给药对血小板聚集的影响。方法：使用超滤的方法以及肝素亲和层析柱HeparinSepharoseCL－6B和凝胶层析柱SephadexG150分高纯化中国眼镜蛇毒蛋白酶。SDS-聚丙烯酰胺凝胶电泳（SDS－PAGE）检测其纯度和分子量。比浊法测定血小板聚集率。结果：从中国眼镜蛇毒中纯化出具有水解纤维蛋白原活性的蛋白酶，经SDS－PAGE电泳测定为一条带，分子量为47.1kD。该蛋白酶低剂量（0．025mg／kg）、中剂量（0．05mg／kg）以及高剂量（0．1mg／kg）体内给药后，剂量依赖性地抑制ADP（10μmol／L）、胶原（100μg／ml）诱导的兔血小板聚集。结论：具有水解纤维蛋白原活性的中国眼镜蛇毒蛋白酶在体内表现出抑制血小板聚集的作用。 OBJECTIVE: To purify proteolytic enzymes from hydrolyzed fibrinogen from Chinese cobra venom, and observe the effect of in vivo administration on platelet aggregation. METHODS: The Chinese cobra venom protease was purified by ultrafiltration using heparin affinity chromatography column HeparinSepharose CL-6B and gel chromatography column SephadexG150. The purity and molecular weight were determined by SDS-polyacrylamide gel electrophoresis (SDS-PAGE). Turbidimetric assay platelet aggregation rate. RESULTS: Protease with hydrolyzed fibrinogen activity was purified from Chinese cobra venom and determined as a band by SDS-PAGE electrophoresis with a molecular weight of 47.1 kD. The low dose (0.025 mg/kg), medium dose (0.05 mg/kg), and high dose (0.1 mg/kg) of the protease dose-dependently inhibited ADP (10 μmol/L), collagen ( 100 [mu]g/ml) induced rabbit platelet aggregation. CONCLUSION: Chinese cobra venom proteases with hydrolyzed fibrinogen activity exhibit inhibitory effects on platelet aggregation in vivo.