蛇毒纤溶酶及自体内皮祖细胞移植对急性心肌缺血/再灌注后心功能的影响

Effects of snake venom fibrinolytic enzyme and transplantation of autologous endothelial progenitor cells on myocardial function after ischemia/reperfusion

目的观察成年白兔自体内皮祖细胞悬液及蛇毒纤溶酶对急性缺血/再灌注所引起心肌损伤的影响和心功能的变化。方法取28只成年新西兰白兔,随机分为4组:对照(A)组(仅注射培养液)、细胞移植(B)组(注射自体内皮祖细胞)、蛇毒纤溶酶(C)组(仅注射蛇毒纤溶酶)、蛇毒纤溶酶+细胞移植(D)组(注射蛇毒纤溶酶和自体内皮祖细胞)。密度梯度离心法分离兔外周血单个核细胞,以EGM-2培养基培养7d,获得兔外周血内皮祖细胞。结扎兔的左冠状动脉建立急性心肌梗死模型,1h后再灌注。分别经主动脉根部注射自体内皮祖细胞悬液及蛇毒纤溶酶。移植术4周后,通过心脏超声对各组实验兔心功能进行检查、记录并行统计学分析。对各组梗死心肌及周围组织、梗死的心室壁进行HE染色,光镜下观察组织学变化。结果所有实验动物缺血后,心电图表现为ST段抬高,再灌注后,ST段缓慢下降。心动超声指标比较,B、D组心功能明显好于C组,而C组心功能明显好于A组,差异有统计学意义(P<0.05)。肉眼观察发现D组心室壁略增厚,其余各组变化不明显。HE染色发现,B、C、D组心肌恢复情况好于A组。结论通过主动脉根部注射内皮祖细胞和蛇毒纤溶酶可以提高兔缺血/再灌注损伤心肌的恢复并改善心功能。

Objective To study the effect of snake venom fibrinolytic enzyme （SVFE） and transplantation of autologous endothelial progenitor cells （EPCs） on myocardial function after ischemia/reperfusion of the myocardium. Methods Twenty-eight adult rabbits were randomly divided into four groups： culture medium control group （A）, cell transplantation group （B）, snake venom plasminogen group （C） and snake venom plasminogenq-cell transplantation group （D）. Mononuclear cells （MNC） were isolated by density-gradient centrifugation from animals＇ peripheral blood and cultured in endothelial growth medium for 7 days to obtain EPCs. The left coronary artery was ligated and then released one hour later to establish myocardial ischemia/reperfusion model. The suspensions of EPCs or SVFE were injected into the aorta at its root of animals in B, C and D groups. The myocardial function was examined, recorded and analyzed by echocardiography four weeks after transplantation. The infarcted myocardium and ventricular wall as well as the surrounding tissue were stained by HE staining, and then observed under light microscope. Results For all the animals, there was elevation of the ST-segment in electrocardiogram after myocardial ischemia, and declined slowly after reperfusion. The myocardial function of B and D groups was better than that of A and C groups. The myocardial function of B, C and D groups was all better than that of A group （P〈0. 05）. Ventrieular wall was thickened slightly in group D, but not in the rest groups. Conclusion The recovery of injured myocardial function by ischemia/reperfusion may be enhanced and improved by transplantation of EPCs and SVFE at the aortic root.