缬沙坦对心力衰竭家兔心肌细胞肌浆网兰尼碱受体的影响

摘要

Objective: To explore sarcoplasmic reticulum ryanodine receptor2 (RyR 2) expression and calcium releasing function in chronic heart failure (CHF) rabbits and to study the impact of long term valsartan treatment in relevant animals. Methods: HF model was established by volume overloading with pressure overloading in experimental rabbits. 27 rabbits were divided into 3 groups: Sham group, HF group and HF+valsartan group. n=9 in each group and the animals were treated for 7 weeks. Left ventricular structure, hemodynamic parameters, expression and functional changes of myocardiocyte sarcoplasmic reticulum RyR 2 were observed and compared among different groups. Results: Compared with Sham group, HF group had increased left ventricular mess index (LVMI), left ventricular end diastolic pressure (LVEDP) and decreased left ventricular shortening fraction, LVEF, all P<0.05. Compared with HF group, HF+valsartan group showed decreased LVMI, LVEDP and increased left ventricular shortening fraction, LVEF, all P<0.05. Sarcoplasmic reticulum RyR 2 expression and calcium releasing function were lower in HF group than Sham group, P<0.05; while they were both higher in HF+valsartan group than HF group, P<0.05. Conclusion: Long term application of valsartan could improve the cardiac function which might be related to increased myocardial sarcoplasmic reticulum RyR 2 expression and calcium releasing function in experimental CHF rabbits.%目的:探讨家兔慢性心力衰竭(心衰)时心肌细胞肌浆网兰尼碱受体(RyR2)表达及其释钙功能的改变以及血管紧张素Ⅱ受体拮抗剂缬沙坦长期干预的意义.方法:27只家兔随机分为三组:假手术组(n=9)、心衰组(n=9)和缬沙坦组(n=9),通过超容量负荷联合压力负荷建立家兔心衰模型,于术后7周观察左心室结构、血流动力学的变化及心肌细胞肌浆网RyR2的表达和功能的改变.结果:与假手术组比较,心衰组左心室重量指数、左心室舒张末压显著升高(P<0.05),左心室短轴缩短率及左心室射血分数明显降低(P<0.05);与心衰组比较,缬沙坦组左心室重量指数、左心室舒张末期压力显著降低(P<0.05),左心室短轴缩短率及左心室射血分数明显升高(P<0.05);心衰组心肌细胞肌浆网RyR2表达和其释钙功能显著低于假手术组(P<0.05);缬沙坦组心肌细胞肌浆网RyR2表达和其释钙功能显著高于心衰组(P<0.05).结论:长期应用缬沙坦能够改善心脏舒缩功能,可能与其增加心肌细胞肌浆网RyR2表达和其释钙功能有关.