cyp2j3基因转染对在体大鼠心肌缺血-再灌注损伤的影响

目的建立在体大鼠过表达cyp2j3基因模型,并观察过表达cyp2j3对心肌缺血-再灌注损伤的影响。方法采用心肌多点直接注射质粒的方法转染cyp2j3基因,实验分为3组:注射0.9%氯化钠注射液(NS组)、空载体质粒组(pcDNA3.1组)和重组质粒组(pcDNA3.1-2J3组),各组18只大鼠。在基因转染2周后各组取6只大鼠处死并取注射部位附近心肌采用RT-PCR、Westernblotting方法检测心肌组织CYP2J3 mRNA、蛋白的表达,其余采用结扎开放左冠状动脉前降支建立心肌缺血-再灌注模型,用BL-420F生物信号采集处理系统记录血流动力学变化,用TTC染色的方法测定心肌梗死面积。结果基因转染2周后,转染pcDNA3.1-2J3组CYP2J3 mRNA及蛋白明显高于NS组及pcDNA3.1组,行心肌缺血-再灌注后转染pcDNA3.1-2J3组能够提高再灌注期左心室收缩末期压(left ventricular end-systolic pressure,LVESP)、左心室内压最大上升下降速率(±LVdp/dtmax),减少缺血期及再灌注期心肌梗死面积(P<0.05)。结论心肌直接注射质粒pcDNA3.1-2J3能够有效转染心肌组织并能够抗心肌缺血-再灌注损伤。

The Effects of Cyp2j3 Gene Transfection on Myocardial Ischemia-reperfusion Injury in Rats in vivo

Objective To observe the expression of cyp2j3 after intramyocardial injection of plasmid pcDNA3.1-2J3 and examine the effects of cyp2j3 gene transfer on myocardial ischemia-reperfusion injury. Methods Fifty-four male Wistar rats were randomly divided into three groups as follows: normal saline NS group, pcDNA3.1 group and pcDNA3.1-2J3 group, 80 μL normal saline or 80 μL pcDNA3.1 or 80 μL pcDNA3.1-2J3(1 g/L) was injected into 4 sites of left myocardium respectively. Two weeks after gene transfection, six rats from each group were sacrificed to determine the expressions of CYP2J3 mRNA and CYP2J3 protein in myocardial tissue by RT PCR and Western blotting respectively. The other rats were subjected to 45 min ischemia and 120 min reperfusion. Cardiac function was recorded by the use of BL-420F instruments. Infarction size was measured by triphenyltetrazolium chloride(TTC) staining. Results Compared with the control group, CYP2J3 mRNA and CYP2J3 protein were overexpressed in pcDNA3.1-2J3 group after two weeks gene transfer via direct injection. Left ventricular end-systolic pressure(LVESP) and left ventricular maximal velocities of contraction and relaxation(±LV dp/dtmax) were significantly increased in pcDNA3.1-2J3 group after 45 min ischemia and 120 min reperfusion. Myocardial infarction size also reduce in gene transfer pcDNA3.1-2J3 group compared with pcDNA3.1 group in I/R model(P<0.05). Conclusion Cyp2j3 can be effectively transferred into the myocardial tissue and express via direct injection pcDNA3.1-2J3 in vivo. Intramyocardial injection of plasmid pcDNA3.1-2J3 can attenuate the myocardial injury induced by ischemia or reperfusion.