Effects of ramipril on ventricular arrhythmia after myocardial infarction in rabbits
- Author:
- No author available
- Journal Title:
- Chinese Journal of Emergency Medicine
- Issue:
- 4
- DOI:
- 10.3760/cma.j.issn.1671-0282.2012.04.015
- Key Word:
- 心肌梗死;单相动作电位;室性心律失常;电生理;跨壁复极离散度;心肌细胞;雷米普利;兔;Myocardial infarction;Monophasic action potential duration;Arrhythmia ventricular;Electrophysiology;TDR;Ventricular myocardium;Ramipril;Rabbits
Abstract： Objective To determine whether specific angiotensin-conventing enzyme inhibitor with ramipril would affect ventricular arrhythmia generation in rabbits after myocardial infarction and discuss the mechanism of its antiarrhymic efficacy.Methods Twenty-four New Zealand rabbits (Wuhan Laboratory Animal Research Center) were separated into 3 groups:sham-operated (SHAM) group (n =8 ),myocardial infraction (MI) group ( n =8) and myocardial infraction with ramipril (RAM) group ( n =8).SHAM group received a median sternotomy without left ventricular coronary artery ligation.MI and RAM groups' rabbits received a median sternotomy followed by left coronary artery ligation. The successful anterior MI was confirmed by elevation of the ST segment with more than 0.2 mV in lead Ⅱ and Ⅲ.After MI,RAM group rabbits were fed with ramipril [ 1mg/ ( kg · d) ]by intragastric administration for 12 weeks.Before and after MI 12 weeks in three groups.Ventricular tachycardia or fibrillation episodes and the monophasic actionpotential duration in epicardium,mid-myocardium and endocardium cadiocytes were recorded.The statistical technique was t-test and ANOVA.Results Ventricular tachycardia or fibrillation episodes were markedly decreased in RAM group than that in MI group after 12 weeks [ (2.6 ± 0.8) vs.(12.4 ± 2.9),P ＜0.05 ].After MI 12 weeks,the action potential duration of repolarization 90％ (APD90) of three-tier ventricular myocytes in MI group was prolonged than that before MI [ (258.2 ±21.1 ) vs.(230.1 ±23.2),( 278.0±23.8 ) vs.(245.8±25.4),(242.6±22.7) vs.(227.0±21.7),P＜0.05]; however,it was not significant difference between before and after MI 12w in RAM group (P ＞ 0.05 ).Moreover,the transmural dispersion of repolarization(TDR) was markedly increased after MI 12w in MI group than in SHAM and RAM group [ (36.2 ± 10.2 ) vs.( 18.7 ± 6.2 ),(24.9 ± 8.7 ),P ＜ 0.05 ]; but the TDR was not significant difference between RAM and SHAM group ( 18.7 ± 6.2 ) vs.( 24.9 ± 8.7 ),P ＞ 0.05].Conclusions Ramipril significantly reduced the malignant arrhythmia incidence in rabbits after MI.Mended the abnormal TDR was the mechanism for ramipril to therapy.
- [1]吕菁君,魏捷,赵冬冬,等.动作电位恢复性质与室颤机制研究[J].2007,(12).
- [2]李泱,马杰,肖建民,等.应用自制复合电极同步记录兔左心室游离壁三层心肌的单相动作电位[J].2003,(2).
- [3]孔一慧,张蕾,张美,等.贝那普利及依贝沙坦对大鼠心肌纤维化的作用[J].2007,(8).
- [4]F, Aimond,J L, Alvarez,J M, Rauzier,etc.Ionic basis of ventricular arrhythmias in remodeled rat heart during long-term myocardial infarction.[J].1999,42(2).
- [5]Charles Antzelevitch,Serge Sicouri.Clinical relevance of cardiac arrhythmias generated by afterdepolarizations: Role of M cells in the generation of U waves, triggered activity and torsade de pointes[J].1994,23(1).
- [6]S, Sicouri,C, Antzelevitch.A subpopulation of cells with unique electrophysiological properties in the deep subepicardium of the canine ventricle. The M cell.[J].1991,68(6).
- [7]Charles Antzelevitch,Serge Sicouri,Silvio Litovsky,etc.Heterogeneity Within the Ventricular Wall Electrophysiology and Pharmacology of Epicardial, Endocardial, and M Cells[J].1991,69(6).
- [8]Emeline, Perrier,Beno?t-Gilles, Kerfant,Nathalie, Lalevee,etc.Mineralocorticoid receptor antagonism prevents the electrical remodeling that precedes cellular hypertrophy after myocardial infarction.[J].2004,110(7).
- [9]Maranga StefanoSdringola,Naccarelli GeraldV,Nisam Seah,etc.Do ACE inhibitors or angiotensin II antagonists reduce total mortality and arrhythmic mortality? A critical review of controlled clinical trials.[J].2002,17(1).
- [10]Martin St John Sutton,Douglas Lee,Jean Rouleau,etc.Left Ventricular Remodeling and Ventricular Arrhythmias After Myocardial Infarction[J].2003,107(20).
- [11]Antzelevitch C,Fish J.Electrical heterogeneity within the ventricular wall.[J].2001,96(6).
- [12]Hicks MN,Kane KA,Cobbe SM,etc.Functional, structural, and dynamic basis of electrical heterogeneity in healthy and diseased cardiac muscle: implications for arrhythmogenesis and anti-arrhythmic drug therapy.[J].1999,84(2).
- [13]M R, Franz.Bridging the gap between basic and clinical electrophysiology: what can be learned from monophasic action potential recordings?[J].1994,5(8).