蝮蛇毒蛋白C激活物对大鼠心肌微血栓形成的抑制作用

目的:观察蝮蛇毒蛋白C激活物(PCA)对大鼠心肌微血栓形成的影响,并进一步探讨其抗凝机制。方法:取健康雄性SD大鼠48只,随机分为假手术(SH)组、微血栓(MI)组、MI+PCA组和PCA组,其中MI+PCA组又分为1mg/kg、3mg/kg、6mg/kg三个剂量组,每组8只。以月桂酸钠复制大鼠心肌微血栓模型,测定并比较各组血浆中PAF、ET-1、vWF、MDA的含量及SOD的活性;心肌石蜡切片,常规HE染色,光镜观察;观察心肌梗死范围。结果:MI+PCA(3mg/kg)组及MI+PCA(6mg/kg)组大鼠血浆中PAF、ET-1、vWF、MDA的含量较MI组显著降低(P<0.05);病理亦显示MI+PCA(3mg/kg)组及MI+PCA(6mg/kg)组心肌无微血管血栓形成、无梗死;PCA组与SH组各指标无明显差异。结论:PCA可有效抑制微血栓形成,其除了可通过激活蛋白C系统抗凝外,保护血管内皮亦可能是其另一抗凝途径。

Inhibitory effects of protein C activator from venom of agkistrodon halys rat with myocardial microthrombus

Objective:To observe the effects of protein C activator from venom of agkistrodon halys on rats with myocardial microthrombus, with further investigation of the anticoagulant mechanisms. Methods: 48 male SD rats were randomly divided into sham operation(SH), microthrombus (MI), protein C activator(PCA)and MI PCA group. MI PCA were subgrouped into 1 mg/kg, 3 mg/kg and 6 mg/kg administered group with 8 rats in each. The model of myocardial microthrombus was induced by sodium laurate for measuring and comparing the contents of vWF, PAF, ET-1, MDA and the activities of SOD in the plasma. The size of myocardial infarction was examined pathologically by using paraffin method, HE staining as well as microscopic observations. Results: Compared with MI group, MI PCA in dose of 3 mg/kg or 6 mg/kg group significantly reduced the contents of vWF, PAF, ET-1 and MDA in the plasma (P<0.05), and no microthrombus and infraction were detected in group of MI PCA with a dose of 3 mg/kg or 6 mg/kg. The levels between SH and PCA group showed no significant difference. Conclusion: PCA purified from venom of agkistrodon halys can evidently inhibit the formation of myocardial microthrombus by activating protein C, also, the effect on protecting vaso-endothelia cells might be responsible for the anticoagulant effect.