血红素加氧酶1基因转染对大鼠离体心肌缺血再灌注损伤的影响

Effects of Adeno-Associated Virus-Mediated Gene Transfection of Rat Heme Oxygenase-1 on Myocardial Ischemia Reperfusion Injury in the Isolated Rat Heart

目的:观察重组腺相关病毒介导血红素加氧酶1(AAV-rHO-1)基因在大鼠心肌的表达情况,及其对大鼠心肌离体缺血再灌注损伤的影响。方法:雄性SD大鼠30只随机分成3组,对照组(C组,n=6),缺血再灌注组(I/R组,n=12),AAV-rHO-1基因组(A-r组,n=12)。基因转染3个月后,半定量RT-PCR检测转染基因的表达情况,并建立大鼠离体心脏Langendorff灌流模型,C组持续灌注100 min,其他各组均平衡15 min,停灌40 min与再灌注45 min,记录各组心功能变化,测定冠脉流出液乳酸脱氢酶(LDH)活性,测定再灌注后45 min时的心肌超氧化物岐化酶(SOD)活性及丙二醛(MDA)含量,同时取每组大鼠心肌检测梗死面积。结果:经半定量RT-PCR分析显示,血红素加氧酶在A-r组心肌中有效表达。离体心肌Langendorff灌注时,与I/R组比较,A-r组在复灌后各时间点心功能明显增强(P<0.01),复灌后冠脉流出液LDH活性降低(P<0.01),复灌后45 min后心肌MDA含量降低(P<0.01),SOD活性增高(P<0.01),梗死面积较小(P<0.01)。结论:腺相关病毒携带的血红素加氧酶1基因能有效地转染心肌组织,并在体内稳定表达,AAV-rHO-1转染预处理对大鼠离体心肌缺血再灌注损伤有显著保护作用。

Objective： To study the rat heme oxygenase-1 （rHO-1） gene transfection carried by adeno-associated virus （AAV） on isolated rat myocardium with ischemia reperfusion injury. Methods： Thirty male SD rats were randomly divided into three groups as control group （n= 6）, ischemia reperfusion group （I/R group, n= 12） and AAV-rHO-1 group （A-r group, n= 12）. The rats were killed at three months after gene transfection. RT-PCR was performed to examine the ex- pression of HO-1, at the same time, the rat hearts were isolated and perfused with Langendorff apparatus. Control group were perfused persistently for 120 min. After being stabilization perfused, the I/R group and A-r group hearts were subjected to 40 min global ischemia and followed by 45 min reperfusion. The variation of heart function were monitored continuously. Coronary effluent was collected for determination LDH activity. At the end of 45 min reperfusion, the hearts were harvested for determination of mycordial SOD activity, MDA content and infarct size. Results. The results of RT-PCR indicated that transgene had already expressed in A-r group. After reperfusion, the hearts function recovered significantly better in A-r group than in I/R group（P〈0.01）, and myocardial MDA content and LDH activity were significantly lower in A r group（P〈0.01）, but the SOD activiy was higher（P〈0.01）. Compared with that in I/R group, the infarct area was significantly smaller in A-r group（P〈0.01）. Conclusion： AAV-rHO- 1 can efficiently transfected in myocardium, and rHO-1 gene was stably expressed in vivo. Adeno-associated virus mediated gene transfection of rHO-1 has significantly protective effect on isolated myocardium after ischemia reperfusion.