雌激素对大鼠心肌缺血再灌注损伤过程中心肌HGF表达的影响

目的 观察17β-雌二醇(E_2)在大鼠心肌缺血再灌注损伤(myocardial ischemia-reperfusion injury,MIRI)过程中对肝细胞生长因子(hepatocyte growth factor,HGF)mRNA的表达影响并探讨其与细胞凋亡的关系.方法 雄性SD大鼠40只,利用随机数字表将其分为缺血再灌注组(即对照组)、17β-雌二醇作用后的缺血再灌注组(即E_2作用组),每组20只.结扎大鼠冠状动脉左前降支20 min,再灌注30 min,造成心肌缺血再灌注损伤模型,观察17β-雌二醇对心肌HGF表达的影响,同时测定心肌细胞的凋亡.结果 心肌缺血20 min及再灌注30 min时,E_2作用组HGF mRNA表达均较对照组相应时点显著增高(P＜0.05).TUNEL法检测E_2作用组再灌注30 min单位面积内心肌细胞凋亡较对照组明显减低(P＜0.05);同时流式细胞仪检测结果显示,E_2作用组亦显著低于对照组(P＜0.05).对照组再灌注30 min及E_2作用组再灌注30 min的HGF mRNA表达变化与相应时间点的心肌细胞凋亡变化成负相关.结论 17β-雌二醇在大鼠心肌缺血再灌注损伤(MIRI)过程中可提高HGF的表达,来发挥抗凋亡作用.

E_2 upregulates HGF mRNA expression in rat heart during myocardial ischemia-reperfusion process

Objective To investigate the effect of 17β-estradiol (E_2) on the expression of hepatocyte growth factor (HGF) mRNA in the myocardial tissues in rats during myocardial ischemia-reperfusion (I/R) process, and explore the relationship between HGF mRNA expression and myocardial apoptosis. Methods U-sing the random number table, 40 male SD rats were divided into 2 groups (20 rats in each group) randomly, ischemia-reperfusion (control) group and E_2 treatment group. Myocardial I/R models of rats were duplicated by ligating the left anterior descending coronary artery for 20 min then reperfusion for 30 min. The expression of HGF and the apoptosis of myocardiocytes were observed with RT-PCR, TUNEL and flow cytometry. Results At the points of cardiac ischemia for 20 min and reperfusion for 30 min, in the E_2 treatment group, the expressions of HGF mRNA were significantly higher than corresponding points of the control group (P <0. 05 ). After reperfusion for 30 min, the number of apoptosis cells per unit area in the E_2 treatment group was significantly lower than the control group. And the apoptosis rate of the E_2 treatment group was also lower than the control group ( P < 0. 05 ). At the point of reperfusion of 30 min, the changing of cardiac HGF mRNA between with E_2 treatment and without had the negative relationship with the changing of apoptosis with the corresponding conditions. Conclusion E_2 can elevate the expression of HGF mRNA during myocardial ischemia-reperfusion process and then exert its protective effects during myocardial ischemia-reperfusion injury.