17β-雌二醇对腹主动脉缩窄大鼠的抗心肌肥厚效应

Effects of 17 β-estradiol on cardiac hypertrophy in rats with abdominal aortic constriction

目的 探讨 17β 雌二醇是否可抵抗大鼠主动脉缩窄诱导的心肌肥厚的发生发展。 方法 10 0只雄性和卵巢切除后的雌性SpragueDawley大鼠随机分为以下几组 :(1)假手术对照组 ;(2 )主动脉缩窄 +安慰剂组 ;(3)主动脉缩窄 +17β 雌二醇组 (17β 雌二醇 10mg缓释剂 ,主动脉缩窄前 48h置入颈部皮下 )。血流动力学和左心室重量 ,左心室壁厚度测量。Northernblot测定左心室组织 β 肌球蛋白重链 (β MHC)、α 肌球蛋白重链 (α MHC)、c fos和心钠素 (ANP)的mRNA水平。结果 17β 雌二醇明显减低大鼠主动脉缩窄诱导增高的收缩压和舒张压水平、左心室重量、左心室重量与体重的比值 ,以及左心室壁厚度 ;17β 雌二醇逆转了增高的 β MHC和c fosmRNA水平 ,增加了α MHC和ANPmRNA的水平。结论 17β

Objective To determine whether 17β estradiol protects against the development of cardiac hypertrophy in rats rendered hypertensive by aortic banding. Methods One hundred intact male and ovariectomized female Sprague Dawley rats were randomized to the following treatment groups: (1) sham operated, (2) aortic banding + placebo, and (3) aortic banding + 17 β estradiol (10 mg slow release pellets implanted 48 h before surgery). Carotid and left ventricular systolic(SBP, LVSP) and diastolic blood pressure(DBP, LVDP), ratio of left ventricular weight to body weight (LVW/BW), left ventricular dp/dt and LV wall thickness (LVWT) were measured. Cardiac expression of c fos, ANP, β myosin heavy chain (MHC) and α MHC mRNA were determined. Results Estradiol significantly attenuated banding induced increases in SBP, DBP and LVW, LVW/BW ratio and LVWT in both male and female rats ( P <0.05), while the placebo had no effect. Estradiol reversed the increase in β MHC and c fos mRNA levels induced by cardiac hypertrophy. Estradiol increased the expression of ANP mRNA in estradiol treated male and female rats subjected to banding ( P <0.01). Estradiol also reversed banding induced decreases in α MHC mRNA levels. Conclusion In male and female rats, 17 β estradiol treatment can prevent the development of hypertensive cardiac hypertrophy induced by aortic banding.