成熟自体心肌细胞移植到心肌梗死区的实验研究

Transplantation of autologous left auricle cardiomyocytes into infarcted myocardium in rabbits

目的:研究成年兔左心耳心肌细胞自体移植到梗死区心肌后的存活情况,及其对周围血供、心律的影响,和对左室功能的改善情况。方法:将成年兔随机分为移植组(n=8)和对照组(n=8),所有成年兔均结扎的冠状动脉前降支,建立心肌梗死模型。4周后获取自体左心耳组织,急性消化分离为单细胞后经DAPI标记后,分别将细胞悬液和培养基注射到移植组和对照组梗死区内。4周后行心电图及超声心动图检查,并取移植区组织进行组织学观察。结果:移植4周后移植组与对照组兔子全部存活。心电图检查显示,移植组心率高于对照组(P<0.05),未见异位心律。超声心动图检查提示,至移植后第4周,移植组左室功能优于对照组。心肌组织切片见对照组梗死区内为典型心梗后改变,移植组梗死区内有“细胞岛”形成,荧光检测证明移植的心耳肌细胞在移植区存活。结论:急性分离的自体左心耳心肌细胞移植到梗死区心肌内可以存活并能够改善左室功能。

Objeetive：To investigate the survival of rabbits receiving autologous left auricle cardiomyocytes transplantation into the infarcted myocardium and to assess the effect of transplantation on the peripheral blood supply, heart rate, and cardiac function. Methods： Healthy adult rabbits were randomly divided into transplantation group （n = 8） and control group （n = 8）. The myocardial infarction （MI） models were established by ligating the left anterior descending arteries in all rabbits. Four weeks later the left auricles were harvested and the auricle cardiomyocytes were isolated and labelled with DAPI ex vivo. Rabbits in the transplantation group were injected with DAPI-labelled cell suspension into the infarcted areas and those in control group received culture medium. All the rabbits were examined by electrocardiogram （ECG） and 2-D ultrasonic cardiogram （UCG） 4 weeks after transplantation. Specimens were harvested from the transplanted areas and observed histologically. Resalts：All rabbits survived 4 weeks after transplantation. ECG showed that the heart rate in transplantation group was faster than that in control group （P〈0.05）, with no ectopic rhythm. UCG showed that the left ventricle function of the transplant group were better than that of the control group. Besides, the infarcted areas in control group showed typical histological changes of myocardial infarction and in the transplantation group there were ＂cell islands＂. Fluorescence detection certified the survival of implanted cells. Conclusion： Isolated autologous left auricle cardiomyocytes can survive after grafted into rabbit ventricular myocardium following myocardial infarction and may improve the left ventricular function.