AGT在高血压合并心肌肥厚大鼠体内表达的研究

The study of expression of AGT in hypertensive rats model combined with myocardial hypertrophy

目的:探讨自发性高血压大鼠(SHR)心肌肥厚与血管紧张素原(AGT)的相关性。方法:选用20只18周龄的雄性SHR,为SHR组;选用20只同龄WKY雄性高血压模型对照大鼠,为WKY组,均饲以标准饲料。对两组大鼠分别于0周和12周时采用无创尾套法测量尾动脉收缩压(SBP)和心率,采用酶联免疫吸附测定(ELISA)法检测血清AGT、AngⅡ浓度,并于光镜、电镜下评估心肌组织超微结构病变。结果:经ELISA法血清检测,SHR组大鼠血清AGT、AngⅡ水平在0周和12周的时间点均显著高于WKY组大鼠,两组比较差异有统计学意义(tAGT=27.94、t=27.29,tAng II=16.20、t=31.33;P<0.05)。存在心肌病变的SHR组大鼠,12周时血清AGT、AngⅡ浓度水平明显高于0周时的浓度水平,2个时间点AGT、AngⅡ浓度水平比较,其差异有统计学意义(t=15.17,t=13.77;P<0.05),且随着心肌肥厚病变严重性的增加,血清AGT、AngⅡ浓度亦增加。结论:AGT与自发性高血压大鼠中心肌病变有一定的相关性,抑制AGT的表达很有可能会为高血压患者中心肌肥厚的防治提供一种新方法。

Objective： To discuss the correlation between myocardial hypertrophy and angiotensinogen （AGT） in spontaneously hypertensive rats （SHR）. Methods： The 20 healthy 18-week-old male SHRs were divided in SHR group and 20 age-matched male Wistar Kyoto rats （WKYs） were divided in WKY group. Both of them were fed with standard diet. The systolic blood pressure （SBP） and heart rate were detected by using noninvasive tail-cuff method in the 0 week and 12th week, respectively. The serum AGT and serum Ang II were detected by ELISA. And the lesion of ultra structure about cardiac muscle tissue were evaluated under light microscope and electron microscope. Results： The results of ELISA indicated that the serum AGT and serum Ang II of SHR group were significantly higher than that of WKY group at 0 week and 12th week （tAGT=27.94, t=27.29, tAngII=16.20, t=31.33; P〈0.05）, respectively. The concentrations of serum AGT and serum AngII of rats with myocardial lesions of SHR group at 12th week were statistically significantly higher than that of SHR group at 0 week （t=15.17, t=13.77, P〈0.05）, respectively. And the concentrations of serum AGT and serum Ang II increased with the increase of the seriousness of myocardial lesions. Conclusion： There might be a certain correlation between AGT and myocardial hypertrophy in spontaneously hypertensive rats. To inhibit the expression of AGT might likely provide a new method for the prevention and cure of patients with hypertension combined with myocardial hypertrophy.