缬沙坦对心力衰竭大鼠心肌细胞钙通道和钠-钙交换体电流的影响  

Effect of valsartan on calcium channel current and sodium-calcium exchanger current in heart failure rats

作　　者：邓春玉[1] 林曙光[1] 吴伟康[2] 钱卫民[1] 阮小薇[1] 吴书林[1] 

机构地区：[1]广东省心血管病研究所临床电生理室 [2]中山大学基础学院病理生理教研室,广东广州510080

出　　处：《中国病理生理杂志》2005年第3期465-469,共5页Chinese Journal of Pathophysiology

基　　金：国家自然科学基金资助项目 (No .30 30 0 4 2 1) ;广东省人民医院基金资助项目 (No.Y0 30 4 1)

摘　　要：目的 :探讨缬沙坦对心力衰竭大鼠心肌细胞钙通道和钠 -钙交换体电流的影响。方法 :结扎大鼠冠状动脉左前降支 8周后 ,复制心力衰竭模型 ,随机分 2组 ,即心力衰竭治疗组与心力衰竭对照组 ,分别用缬沙坦和安慰剂治疗 ,另设假结扎对照组。治疗 16周后 ,用急性酶解法获得单个大鼠心室肌细胞和标准全细胞膜片钳技术记录通道电流。结果 :(1)心力衰竭对照组左室舒张末压 (LVEDP)和细胞膜电容 (Cm)明显大于假结扎对照组 (P <0 0 5 ) ,左室最大收缩压 (LVSP)和左室内压的最大上升和下降速率 (±dp/dtmax)明显少于假结扎对照组 (P <0 0 5 ) ;而心力衰竭治疗组LVSP和±dp/dtmax明显高于心力衰竭对照组 (P <0 0 5 ) ,LVEDP和Cm明显少于心力衰竭对照组 (P<0 0 5 ) ,3组心率 (HR)和血压 (BP)无明显差异 (P >0 0 5 )。 (2 )心力衰竭对照组钙通道电流密度峰值明显少于假结扎对照组 (P <0 0 5 ) ,心力衰竭治疗组明显大于心力衰竭对照组 (P <0 0 5 ) ,但激活电位、峰电位和翻转电位差异均无显著 (P >0 0 5 )。 (3) 3组钙通道电流激活、失活和复活动力学特征均无显著差异 (P >0 0 5 )。 (4)心力衰竭对照组钠钙交换体电流密度明显大于假结扎对照组 (P <0 0 5 ) ,心力衰竭治疗组明显少于心力衰竭对照组 (P <0 0AIM: To determine the effects of valsartan on calcium channel and sodium-calcium exchanger current in isolated ventricular myocytes of congestive heart failure (CHF) rats. METHODS: Eight weeks after coronary ligation, the rats with heart failure were confirmed by measuring the hemodynamic parameters and divided randomly into the group treating with valsartan (CHF-T, 20 mg/kg) and placebo (CHF-C). Sham-operated group rats served as negative controls (PS). Twelve weeks later, 6 rats were selected randomly for the study of ion channel. Single ventricular myocytes of rats were isolated by enzymatic dissociation. The whole-cell patch-clamp recording technique was used to record calcium channel current and sodium-calcium exchanger current. RESULTS: (1) In the hemodynamic variables, HR and blood pressure were not significantly different in three groups. Compared CHF-C with PS group, LVEDP and Cm increased, LVSP and ±d p /d t max decreased ( P <0 05). Compared CHF-T group with CHF-C group, LVEDP and Cm decreased, LVSP and ±d p /d t max increased ( P <0 05). (2) Calcium channel current in CHF-C decreased significantly ( P <0 05). Calcium channel current in CHF-T group was larger significantly than that in CHF-C group ( P <0 05). (3) The activation, inactivation and recovery curves were not altered in 3 groups ( P >0 05). (4) Na +-Ca 2+ exchanger current in CHF-C group increased significantly. Na +-Ca 2+ exchanger current in CHF-T group was smaller significantly than that in CHF-C group. However, CHF-T group and PS group were not significantly different. CONCLUSION: Administration of valsartan is effective in preventing from cardiac function deterioration, increases calcium channel current and decreases Na +-Ca 2+ exchanger current in ventricular myocytes of heat failure rats.

关 键 词：心力衰竭 缬沙坦 钠钙交换蛋白 钙通道 

分 类 号：R363[医药卫生—病理学]