心肌梗死大鼠心肌组织中AQP1、HIF-1α的表达变化及其与心肌水肿的关系

Changes of expressions of myocardial AQP1 and HIF-1α and relationship between them and myocardial edema in rats with myocardial infarction

目的观察大鼠心肌梗死模型中心肌梗死组织中水通道蛋白1(AQP1)和缺氧诱导因子-1α(HIF-1α)的表达水平,并探讨其与心肌水肿的相关性。方法将48只SD大鼠随机分为心肌梗死组和假手术组,每组24只。采用结扎左冠状动脉前降支法建立大鼠心肌梗死模型,假手术组仅开胸不结扎。于造模后12、24、48、72 h分批处死大鼠,取左心室心肌组织,采用酶联免疫法检测AQP1、HIF-1α的蛋白表达水平,采用Real-time PCR检测AQP1、HIF-1αmRNA表达,采用干湿重法检测心肌组织含水量。结果心肌梗死组大鼠心肌组织中AQP1、HIF-1αmRNA以及蛋白水平较假手术组明显升高,差异有统计学意义(P均<0.05)。心肌梗死组大鼠心肌组织AQP1、HIF-1αmRNA以及蛋白水平在术后72 h内呈时间梯度升高,各时间点差异具有统计学意义(P均<0.05)。心肌梗死组大鼠术后12、24、48、72 h心肌组织含水量逐渐升高,与假手术组比较也升高,差异有统计学意义(P均<0.05)。心肌梗死大鼠心肌组织中AQP1 mRNA以及蛋白水平与心肌含水量呈正相关(r=0.507,P=0.010;r=0.585,P=0.008),HIF-1αmRNA以及蛋白水平与心肌含水量呈正相关(r=0.408,P=0.025;r=0.486,P=0.017)。结论心肌梗死大鼠心肌组织中AQP1、HIF-1α呈高表达,且与心肌水肿严重程度明显相关。

Objective To observe the expressions of aquaporin（AQP）; hypoxia-inducible factor 1α（HIF-1α） in myocardial infarction tissue, and discuss the correlation between them and myocardial edema in rat model of myocardial infarction（MI）. Methods SD rats（n=48） were randomly divided into MI group and sham-operation group（each n=24）. The rat model of MI was established by using ligation of left anterior descending coronary artery in MI group, and only thoracotomy without ligation in sham-operation group. The rats were killed in batches to collect left ventricular myocardial tissue after modeling for 12 h, 24 h, 48 h and 72 h. The protein expressions of AQP1 and HIF-1α were detected by using ELISA. The mRNA expressions of AQP1 and HIF-1α were detected by using real-time fluorescence quantitative polymerase chain reaction（RT-PCR）. The water content in myocardial tissue was detected by using dry-wet method. Results The protein and mRNA expressions of AQP1 and HIF-1α increased significantly in MI group than those in sham-operation group（all P0.05）. The protein and mRNA expressions of AQP1 and HIF-1α increased in a time gradient in MI group after operation for 72 h, and difference at all time points had statistical significance（all P0.05）. Water content increased gradually in MI group after operation for 12 h, 24 h, 48 h and 72 h, and increased compared with sham-operation group（all P0.05）. The protein and mRNA expressions of AQP1 were positively correlated to myocardial water content（r=0.507,P=0.010;r=0.585,P=0.008） and protein and mRNA expressions of HIF-1α were positively correlated to myocardial water content（r=0.408,P=0.025;r=0.486,P=0.017）. Conclusion AQP1 and HIF-1α show high expressions in myocardial tissue, and are correlated closely to severity of myocardial edema in MI rats.