自拟强心汤对心梗后心力衰竭大鼠心肌舒缩功能的实验研究

摘要

目的：探讨自拟强心汤对心梗后心力衰竭大鼠心肌舒缩功能的作用机制。方法：采用结扎左冠状动脉法制备大鼠心梗后慢性心力衰竭动物模型；8周后，给予药物灌胃治疗；经治疗4周后，采用通过颈动脉插管测定大鼠血流动力学状态，通过实时荧光定量PCR（ FQ-PCR）法和Western Bolt 法检测心肌钙调控蛋白肌浆网钙泵（ SERCA2a）、雷尼丁受体2（ RYR2） mRNA水平及其蛋白表达量。结果：模型组大鼠的心功能显著下降，主要表现在血流动力学参数改变，其中左室舒张末期压（LVEDP）明显升高（P＜0.01），左室收缩压（LVSP）、左室上升最大速率（＋LVdp／dtmax）及左室下降最大速率（-LVdp／dtmax）绝对值均降低（P＜0.05）；心肌钙调控蛋白SERCA2a、RYR2 mRNA水平及其蛋白表达量均明显下降（P＜0.05）。给予自拟强心汤干预后，能够有效的降低心力衰竭大鼠LVEDP水平（P＜0.05），升高LVSP、＋LVdp／dtmax、-LVdp／dtmax水平（P＜0.01）；能够升高心肌钙调控蛋白SERCA2a、RYR2 mRNA及其蛋白表达量的水平（P＜0.05）。结论：自拟强心汤能够有效的改善心力衰竭大鼠的心功能，其机制可能与升高心肌钙调控蛋白SERCA2a、RYR2的蛋白表达量，改善钙循环有关。%Objective:To clarify myocardial systolic and diastolic function and possible mechanism of Qiangxin Tang on the model of heart failure.Methods:Model of heart failure after myocardial infarction was prepared by left coronary artery ligation .After 8 weeks ,take a lavage treatment every day;After 4 weeks of continuous administration ,cardiac hemodynamics parameters were recor-ded and SERCA2a,RYR2 mRNA level were detected by PCR(FQ-PCR)and SERCA2a,RYR2 protein expression were detected by Western bolt.Results:compared with control group ,cardiac function of model group is lower:hemodynamic parameters LVEDP is increased obviously(P<0.01),LVSP,+LVdp/dtmax and-LVdp/dtmax absolute values were all lower (P<0.05),and the calm-odulin SERCA2a and RYR2 mRNA and protein relative expression of model group rats was decreased (P<0.05).Compared with model group,Qiangxin Tang group could reduce LVEDP levels (P<0.05),increase LVSP,+LVdp/dtmax and-LVdp/dtmax levels (P <0.01 ), and the calmodulin SERCA2a and RYR2 mRNA and protein relative expression of Qiangxin Tang were higher.Conclusion:Qiangxin Tang can effectively improves cardiac function in heart failure rats;Its mechanism is related with im-proving calmodulin SERCA2a、RYR2 and improving calcium cycle .