Effect of carvedilol on monophasic action potential and refractory period of isolated heart in rats with healed myocardial infarction
- Author:
- No author available
- Journal Title:
- CHINESE JOURNAL OF EMERGENCY MEDICINE
- Issue:
- 3
- DOI:
- 10.3760/j.issn:1671-0282.2008.03.003
- Key Word:
- 心肌梗死;卡维地洛;单相动作电位;有效不应期
Abstract： 目的 观察陈旧性心肌梗死(HMI)大鼠离体心脏单相动作电位(MAP)及心室有效不应期(ERP)的变化及卡维地洛对其影响.方法 制作大鼠MI模型,术后24 h存活大鼠24只随机分为卡维地洛组(Car组)和HMI组,分别给予卡维地洛(10mg·kg-·d-1)及安慰剂.另行假手术为对照组(n=10),只穿线不结扎.HMI组和假手术组大鼠给予等量蒸馏水灌胃.8周后行血流动力学测定;Langendorff离体心脏灌流,记录大鼠左心室前壁梗死边缘区(IBZ)的MAP,测量动作电位振幅(APA及20%、50%和90%MAP复极时程(MAPD20、MAPD50和MAPD90);测定心室ERP.数据用均数±标准差(x±s)表示,统计分析采用单因素方差分析,组问比较采用SNK法,以P＜0.05为差异具有统计学意义.结果 与假手术组(5.02±1.92)mmHg相比,HMI组左室舒张末压(LVEDP)(29.66±5.57)mmHg显著增加,左室内压最大收缩和舒张速率(±dp/dtmax)显著降低;MAPD20(17.2±3.8)ms、MAPD50(43.7±7.8)ms、MAP90抑(94.8±7.9)ms及ERP(75.6±10.7)ms均明显延长,APA(3.75±0.70)mV下降.给予卡维地洛后,与HMI组相比,LVEDP显著降低,±dp/dtmax显著升高;MAPD20、MAPD50、MAPD90及ERP均较HMI组缩短,APA较HMI组增加.Vmax在各组差异无显著性.结论 卡维地洛能改善大鼠MI后的血流动力学变化,抑制MI后MADP20、MAPD50、MAPD90及ERP延长,可能是其防治恶性室性心律失常的机制.
- [1]钮伟真,叶刚,刘萍.介绍一套小动物离体灌流心脏心电信号研究设备[J].2000,(2).
- [2]LI Xun,JIANG Wenping.Electrical remodeling of membrane ionic channels of hypertrophied ventricular myocytes from spontaneously hypertensive rats[J].2000,(7).
- [3]牛惠燕,刘念,李泱,等.早期口服卡维地洛对兔陈旧性心肌梗死边缘带不应期和钠电流的影响[J].2005,(3).
- [4]孙益兰,牟云,王利宏,等.不同剂量卡维地洛对急性心肌梗死大鼠左室重构及血流动力学的影响[J].2005,(7).
- [5]喜杨,曲秀芬,于彦伟,等.心肌梗死后交感神经的重构现象[J].2004,(3).
- [6]LI Xia,HUANG Cong-xin,JIANG Hong,etc.The beta-adrenergic blocker carvedilol restores L-type calcium current in a myocardial infarction model of rabbit[J].2005,(5).
- [7]丁超,何振山,崔俊玉,等.急性心肌梗死1周和8周后心室肌细胞瞬间外向钾电流的变化[J].2003,(5).
- [8]周宇宏,单宏丽,董德利,等.抗心律失常药物作用的新靶点[J].2002,(5).
- [9]Patten RD,Konstam MA,Hanak GG,etc.Ventricular remodeling in a mouse model of myocardial infarction.[J].1998,274(5 Pt.2).
- [10]Dayi Qin,Zhi-Hao Zhang,Edward B. Caref,etc.Cellular and Ionic Basis of Arrhythmias in Postinfarction Remodeled Ventricular Myocardium[J].1996,79(3).
- [11]Kane KA,Cobbe SM,McIntosh MA,etc.Action potential prolongation and potassium currents in left-ventricular myocytes isolated from hypertrophied rabbit hearts.[J].1998,30(1).
- [12]Gao R,Tang Y,Ruan Y,etc.Comparison of metoprolol with low, middle and high doses of carvedilol in prevention of postinfarction left ventricular remodeling in rats.[J].2003,44(6).
- [13]Brooks A,Kass RS,Liang C,etc.Overexpression of nerve growth factor in the heart alters ion channel activity and beta-adrenergic signalling in an adult transgenic mouse.[J].1998,512(Pt.3).