五步蛇毒PCA在心肌缺血再灌注损伤诊断中的实验研究

Protein C activator from Agkistrodon Acutus venom in diagnosis of myocardial ischemia reperfusion injury: Experimental study

目的:探讨五步蛇毒蛋白C激活剂(Protein C activator,PCA)在心肌缺血再灌注损伤诊断中的应用。方法:SD大鼠随机分成对照组(control,C组)和缺血再灌注损伤组(Ischemia reperfusion injury,IR组),每组15只。IR大鼠开胸结扎左冠状动脉前降支30 min后再灌注120 min,C组大鼠只穿线而不结扎左冠状动脉前降支;记录大鼠在体心电图及心肌组织学改变。留取血液以制备血浆,检测其活化部分凝血酶时间(activated partial thromboplastin time,APTT);以发色底物法检测血浆蛋白质C(Protein C,PC)活性;酶联免疫吸附法检测血浆游离蛋白质S(plasma free protein S,FPS)的含量。结果:同C组相比,IR组大鼠心肌横纹模糊不清或消失,肌纤维及肌丝明显紊乱且心电图改变明显;IR组大鼠心脏再灌注60 min后血浆APTT明显缩短(P<0.05),血浆PC活性缺血期间明显下降,再灌注60 min明显回升,而再灌注120 min又再次下降(P<0.01);血浆FPS含量缺血期间明显减少,再灌注60 min升高,再灌注120 min又减少(P<0.05,P<0.01)。结论:以五步蛇毒PCA制备的血浆蛋白C活性检测试剂可较灵敏地反映心肌缺血再灌注损伤大鼠血浆蛋白C活性的变化。

Objective：To investigate the protein C activator （ PCA） extracted from the Agkistrodon Acutus venom in the diagnosis of myocardial ischemia reperfusion injury.Methods：Sprague-Dawley（ SD） rats were randomly divided into control group （ group C） and ischemia reperfusion injury group （ group IR）（n=15 for each）.The left anterior descending coronary arteries of the rats in group IR were ligated via open surgery for 30 min and undergone perfu-sion for 120 min.A silk thread was applied through the left auricle for the rats in group C without artery ligation .In vivo dynamic electrocardiogram was performed and myocardial histological changes were examined to determine whether the model was successfully established .Then the blood was obtained for plasma preparation to measure the activated partial thromboplastin time （ APTT） .Chromomeric substrate assay was performed to protein C （ PC） activity, and enzyme linked immunosorbent assay（ELISA） was used to determine the plasma free protein S（FPS）.Results：As compared with the control group,the cardiac muscle cross striations were faint or vanished ,and the muscle fibers and filaments were in visually disordered manner with significant ECG changes for the rats in group IR.After reperfusion for 60 min,the APTT was significantly shortened（P〈0.05）,and the plasma PC activity was significantly de-creased at ischemia.However,elevated PC activity was observed by reperfusion for another 60 min and down-regulated by reperfusion for 120 min （ P 〈0.01）.The plasma FPS level was evidently increased in ischemia condition,yet elevated by reperfusion for 60 min and fallen at 120 min of reperfusion （P〈0.05;P〈0.01）.Conclusion：PCA excreted from the Agkistrodon Acutus venom may sensitively indicate the changes of plasma PC in rats with myo-cardial ischemia reperfusion injury.