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-1α mRNA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-1α mRNA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-1α mRNA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-1α mRNA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 P<0.05). 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 P<0.05). 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 P<0.05). 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.