洛沙坦和安体舒通对肾血管性高血压大鼠心血管肥厚的作用

Effect of Losartan and Spironolactone on Cardiovascular Hypertrophy in Renovascular Hypertensive Rats

目的：观察洛沙坦（ｌｏｓａｒｔａｎ）和安体舒通（ｓｐｉｒｏｎｏｌａｃｔｏｎｅ）对肾血管性高血压大鼠高血压、左心室和主动脉壁肥厚的预防作用，并探讨其心血管肥厚与心肌血管紧张素Ⅱ（ＡｎｇⅡ）及血浆醛固酮之间的关系。方法：随机分４组，将二肾一夹型肾血管性高血压大鼠从术后开始分别给予洛沙坦（二肾一夹型＋洛沙坦组）和大剂量安体舒通（二肾一夹型＋安体舒通组），与假手术组和不给药二肾一夹型组大鼠作为对照。术前及术后每２周测血压１次，术后６周时进行左心室重量指数（ＬＶＭＩ）、心肌ＡｎｇⅡ含量和主动脉中膜／内径比值的测定，同时用放射免疫法测定血浆ＡｎｇⅡ和醛固酮浓度。结果：二肾一夹型组大鼠血压持续性升高，左心室重量指数和主动脉中膜／内径比值增加；二肾一夹型＋洛沙坦组的血压、左心室重量指数和主动脉中膜／内径比值与假手术组无差异；二肾一夹型＋安体舒通组的血压低于二肾一夹型组，但高于假手术组，左心室重量指数和主动脉中膜／内径比值高于假手术组，但比二肾一夹型组低。相关分析表明左心室重量指数和主动脉中膜／内径比值与收缩压、心肌ＡｎｇⅡ含量呈正相关。结论：洛沙坦可预防二肾一夹型组大鼠的心血管肥厚，大剂量安体舒通仅部分预防其心血管肥厚，二?

Objective:To investigate the preventive effects of losartan and spironolactone on hypertension,left ventricular and aortic hypertrophy in renovascular hypertensive rats and the relative importance of plasma aldosterone and cardiac angiotensin Ⅱ (Ang Ⅱ) in cardiovascular hypertrophy. Methods:Two kidney 1 clip(2K1C) rats were treated with losartan or large dose of spironolactone immediately after operation.Sham operated and nontreated 2K1C rats were as controls.Blood pressure were measured before and every 2 weeks after operation.Left ventricular mass index (LVMI) and aortic media/lumen ratio were determined at 6 weeks after operation.Myocardial Ang Ⅱ content and plasma Ang Ⅱ,aldosterone concentration were also determined by radioimmunoassay. Results:There was a sustained elevation of blood pressure,increase of LVMI and aortic media/lumen ratio in 2K1C rats.In 2K1C rats treated with losartan the blood pressure did not increase with normal LVMI and aortic media/lumen ratio;while in those treated with spironolactone,the blood pressure,LVMI and aortic media/lumen ratio were lower than in nontreated group but higher than in sham operated group.Correlative analysis revealed that LVMI and aortic media/lumen ratio were both positively correlated with systolic blood pressure and cardiac Ang Ⅱ content. Conclusions:Losartan could prevent cardiovascular hypertrophy in 2K1C rats and large dose of spironolactone couldonly partly do it.Myocardial Ang Ⅱ may contribute to cardiovascular hypertrophy in 2K1C rats.