β受体阻断剂对大鼠急性心肌梗死后G蛋白及心功能的影响  

The effect of β-adrenoceptor blockers on G protein and heart function in rats with acute myocardial infarction

作　　者：谢荣盛[1] 富路[1] 曹君娴[1] 戴颖楠[1] 朱立群[1] 韩颖[1] 

机构地区：[1]哈尔滨医科大学第一临床医学院心内科,150001

出　　处：《中华老年医学杂志》2009年第8期692-695,共4页Chinese Journal of Geriatrics

摘　　要：目的观察β受体阻断剂对大鼠急性心肌梗死（AMI）后G蛋白及心功能变化的影响。方法复制大鼠AMI模型，随机分3组，分别给予选择性β1受体阻断剂美托洛尔（美托洛尔组）、非选择性β受体阻断剂卡维地洛（卡维地洛组）及安慰剂（对照组），另设假手术组。8周后测定AMI后血流动力学变化；采用Western印迹杂交法研究兴奋性G蛋白（Gs）和抑制性G蛋白（Gi）的变化。结果与假手术组比较，AMI组主动脉收缩压（SBP）、主动脉舒张压（DBP）、左心室收缩压（LVSP）、左心室内压最大收缩和舒张速率（±dp／dtmax）均显著下降，左心室舒张末压（LVEDP）显著升高[（6．0±2，9）mmHg与（29．7±5．6）mmHg3；Gs蛋白分别为（101．9±3．5）％和（115．9±11．2）％，Gi蛋白显著升高[分别为（102．5±4．9）％和（238．4±68．0）％]。与AMI组比较，美托洛尔、卡维地洛组LVSP、±dp／dtmax升高，LVEDP下降[（10．3±4．9）mmHg、（7．9±3．8）mmHg3；Gi显著下降，分别为（128．1±17．2）％与（104．5±13．7）％。卡维地洛组LVEDP和Gi下降较美托洛尔组明显。结论卡维地洛能有效抑制AMI后G蛋白的变化并改善心功能，且优于美托洛尔，可能与其β2受体阻断作用有关。Objective To investigate the effect of β-adrenoceptor （β-AR） blockers on G protein and heart function changes in rats with acute myocardial infarction （AMI） Methods Wistar rats with AMI induced by left anterior descending coronary branch ligation were randomly divided into metoprolol （20 mg· kg^- 1 · d^- 1） group, carvedilol （10 mg · kg^-1· d^-1） group and control group. compared with sham operation group. Eight weeks after therapy, hemodynamics was assessed by inserting catheters and the level of G protein was detected by Western blot analysis. Results Compared with the sham operation group, systolic blood pressure（SBP）, diastolic blood pressure （DBP）, left ventricular systolic pressure（LVSP） and left ventricular pressure maximal rate of rise and fall（± dp/dtmax） in AMI group were significantly decreased, while left ventricular end diastolic pressure （LVEDP） and Gs and Gi protein levels were significantly increased （all P〈0.05）. Compared with AMI group, LVSP and ± dp/dtmax were increased, but LVEDP and Gi protein level were significantly decreased in metoprolol and carvedilol group. LVEDP and Gi protein level were decreased in carvedilol group compared with metoprolol group. Conclusions Carvedilol can effectively suppress the change of G protein and improve the heart function after AMI, and the effect is better than that of metoprolol. This may be related with its β2-AR blocking effect.

关 键 词：心肌梗死 血流动力学 Β肾上腺素能受体 G蛋白 

分 类 号：R686[医药卫生—骨科学]