不同时期高血压大鼠心肌组织eNOS及Ser1179活性变化

Changes of eNOS and Ser1179 activity in myocardial tissue of hypertensive rats at different stages

目的 通过观察不同时期高血压大鼠心肌组织内皮型一氧化氮合酶（eNOS）表达及其相关调控位点Ser1179磷酸化水平、NOS活性和NO产量变化,来探讨血压变化对心肌组织eNOS活性的影响.方法 将24只SD大鼠随机分为四组,假手术2W、4W组和高血压2W、4W组,每组6只,采用双肾双狭（2K2C）复制肾血管性高血压大鼠模型.鼠尾测压法测定大鼠血压；Western Blot分别检测大鼠心肌组织eNOS、P-NOS（P-Ser1179）蛋白表达；心肌组织NO测定采用硝酸还原酶法.结果 与假手术组相比,术后2周时,RH大鼠心肌组织eNOS蛋白表达及Ser-1179磷酸化水平无明显变化（P＜0.05）；术后4周时,RH大鼠心肌组织eNOS蛋白表达、Serl179磷酸化水平显著提高（P＜0.01）.结论 肾血管性高血压大鼠心肌组织存在着eNOS蛋白表达及活性变化,eNOS具有重要的代偿调节作用,可能与血压升高刺激Serl179的磷酸化水平升高,上调NOS活性有关.

Objective To observe endothelial nitric oxide synthase （eNOS） protein expression in myocardial tissue of hypertension rats at different periods and its related regulation with loci Ser1179 phosphorylation levels,NOS activity and NO yield changes,to explore the relationship between blood pressure and eNOS in myocardial tissue.Methods 24 SD rats were randomly divided into four groups,control group 2 w,4 w and hypertension group 2 w,4 w,6 in each group,producing two-kideny two-clip renovascular hypertensive rats model （2k2c RH model）.Blood pressure of rats was detected by rat tail pressure measuring method,eNOS,P-NOS （P-Ser1179） protein expression in myocardial tissue by Western Blot,NO in myocardial tissues by nitrate reductase method.Result Compared with the control group,eNOS protein expression and Ser1179 phosphorylation level in myocardial tissue of RH rats didn＇t obviously change after 2 weeks （P ＞ 0.05）,but increased significantly after 4 weeks （P ＜ 0.01）.Conclusions 2k2c RH rats myocardial tissue exists eNOS changes in protein expression and activity,has an important compensatory eNOS adjust action,which may be related to stimulation of Ser1179 phosphorylation level and NOS activity caused by increased blood pressure.