cyp2j3基因转染对在体大鼠心肌缺血-再灌注损伤的影响

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

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。

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（P0.05）.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.