氯沙坦逆转自发性高血压大鼠心血管肥厚作用的研究

Effect of losartan on reversing cardiovascular hypertrophy in spontaneous hypertensive rats

目的 :探讨氯沙坦逆转心血管肥厚的作用与心血管局部组织中内皮素 (ET)的关系。方法 :1 6周龄的自发性高血压大鼠 (SHR)随机分成氯沙坦治疗组 (SHR L)与对照组 (SHR C)。另设同源正常血压大鼠 (WKY)组 ,饲养共 6周。大鼠的收缩压和心率用尾套法测量 ,左室重量指数 (LVI)及主动脉中膜与内径比率用测微计测量 ,血浆、心肌和主动脉含量用放免法测定。以SHR C组做直线相关分析。结果 :氯沙坦能显著降低SHR的收缩压 ,SHR L与SHR C组比较LVI及主动脉中膜与内径比值下降 ,左室及主动脉ET ,SHR C组高于WKY组 ,且分别与LVI及主动脉中膜和内径比值呈正相关。结论 :左室及主动脉组织中ET升高是造成左室及主动脉肥厚的重要因素 。

Objective:To investigate the effect of losartan on reversing cardiovascular hypertrophy and ET contents.Methods:16 week old SHR were divided into two groups:SHR L(treated with losartan) and SHR C(untreated).Aged matched Wistar Kyoto(WKY) rats were served as controls.All rats were observed for 6 weeks. Systolic blood pressure and heart rate were measured by a tail cuff method.Left ventricular mass index(LVI) and aortic media/lumen ratio were measured as the indicators of left ventricular and aortic hypertrophy.ET contents were determined by radioimmunoassay.Results:Losartan significantly lowered systolic blood pressure.LVI and aortic media/lumen ratio were reduced in SHR L compared with SHR C.Left ventricular and aortic ET were higher in SHR C than WKY and positively correlated with LVI and aortic media/lumen respectively.Conclusion:The locally increased ET may contribute to the cardiovascular hypertrophy and losartan reverse cardiovascular hypertrophy by blocking AT receptor and reducing ET content in plasma and cardiovascular tissues.