雷米普利对兔心肌梗死后心室肌短暂外向钾电流变化的影响  

The effect of ramipril on myocardial infarction in rabbit ventricular myocytes transient outward potassium effect of current changes

作　　者：陈志楠[1] 丁世芳[1] 龚志刚[1] 卢青[1] 

机构地区：[1]广州军区武汉总医院心内科,430070

出　　处：《中国医药》2013年第10期1377-1379,共3页China Medicine

摘　　要：目的探讨血管紧张素转化酶抑制剂雷米普利对兔心肌梗死后室性心律失常发生的影响及其可能机制。方法将24只家兔完全随机分为假手术组、心肌梗死组和雷米普利组，每组8只。3组均在无菌条件下开胸，其中心肌梗死组和雷米普利组分别结扎左冠状动脉前降支。雷米普利组术后第2天给予雷米普利1mg／（kg·d）灌胃，3组均喂养12周。3组家兔分别在心肌梗死前、心肌梗死后12周记录程序刺激诱发的室性心动过速／心室颤动（VT／VF）发生次数，并采用全细胞膜片钳技术记录短暂外向钾电流（Ito）的变化。结果心肌梗死后12周，雷米普利组VT／VF的发生次数明显低于心肌梗死组[（3．0±0．6）比（12．7±1．5），P〈0．05]；假手术组、心肌梗死组和雷米普利组Ito电流密度分别为（8．69±0．57）pA／pF、（4．71±0．43）pA／pF和（7．32±0．68）pA／pF，心肌梗死组显著高于假手术组及雷米普利组（P〈0．05）；雷米普利组与假手术组比较差异无统计学意义（P〉0．05）。结论长期服用雷米普利可明显降低家兔心肌梗死后VT／VF的发生，其机制可能与抑制家兔心肌梗死后It0有关。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.

关 键 词：心肌梗死 室性心律失常 短暂外向钾电流 膜片钳 雷米普利 

分 类 号：R540.41[医药卫生—心血管疾病]