The effect of ramipril on myocardial infarction in rabbit ventricular myocytes transient outward potassium effect of current changes
CHEN Zhi-nan
DING Shi-fang
GONG Zhi-gang
LU Qing
Abstract：Objective To determine whether ramipril,a specific angiotensin-conventing enzyme inhibitor would affect arrhythmia generation in rabbits after myocardial infarction.Methods Twenty-four rabbits were divided into 3 groups:sham-operated (SHAM) group (n =8),myocardial infraction (MI) group (n =8) and ramipril (RAM) group (n =8).SHAM group rabbits received a median stemotomy without left ventricular coronary artery ligation.MI and RAM group rabbits received a median sternotomy followed by left coronary artery ligation.After MI,RAM group rabbits were fed with ramipril (1 mg/kg · d) for 12 weeks.After 12 weeks,myocytes were isolated from the border zone of infracted left ventricular wall and the transient outward potassium current was recorded by whole-cell patch clamp technique.Results Ventricular tachycardia or fibrillation (VT/ VF) episodes were markedly decreased in RAM group than that in MI group (3.0 ± 0.6 vs 12.7 ± 1.5,P ＜ 0.05) after 12 weeks.The density of Ito was lower in MI group than that in SHAM and RAM groups [(4.71 ± 0.43) pA/pF vs (8.69 ± 0.57) pA/pF and(7.32 ±0.68) pA/pF,P ＜ 0.05],however,there were not significant difference between SHAM and RAM groups (P ＞ 0.05).Conclusions Ramipril can reduce the VT/VF episodes in rabbits after MI.This effect of ramipril may be related to inhibited electrical remodeling after MI.
Keywords：Myocardial infarctionVentricular arrhythmiasTransient outwardpotassium currentPatch clampRamipril
Publication Date：2013-10-30
Online Publishing Date：2026-09-14(First online date of this platform, not the publication date of the document)
Pages：3( 1377-1379 )