咪达普利对家兔陈旧性心梗跨室壁动作电位不均一性的影响  

Effects of Imidapril on the Transmural Dispersion of Repolarization in Healed Myocardial Infarction Rabbit

作　　者：高玉玲[1] 王琳[1] 文毅[1] 徐斌[1] 李泱[1] 

机构地区：[1]解放军总医院老年心血管病研究所,北京市100853

出　　处：《中国康复理论与实践》2006年第9期785-787,共3页Chinese Journal of Rehabilitation Theory and Practice

摘　　要：目的研究咪达普利对陈旧性心肌梗死家兔非心梗区心室肌复极离散度的影响。方法取家兔结扎左心室冠状动脉前降支8周后,记录其单相动作电位;采用二步消化法分离左心室游离壁3层心肌细胞。用膜片钳全细胞模式记录单细胞动作电位。结果陈旧性心肌梗死家兔非心梗区心室肌中层的动作电位时程(MAPD90)明显延长,而内膜下和外膜下心肌细胞动作电位时程延长不明显,3层心肌的跨室壁复极不均一性增加。在体单相动作电位的离散度较单细胞动作电位要小。应用咪达普利后,其复极不均一性得到改善,室颤阈值上升。结论咪达普利可降低家兔非心梗区心室肌复极离散度,这可能是其减少陈旧性心肌梗死恶性心律失常发生的机制之一。Objective To investigate the effects of imidapril on the transmural dispersion of repolarization of the noninfarcted myocardium of rabbits after myocardial infarction. Methods Rabbits with left coronary artery ligation were prepared and allowed to recover for 8 weeks. Monophasic action potentials of three layers myocardium in the noninfarcted myocardium in vivo were recorded. Myocytes were isolated from subendocardial, midmyocardial and subepicardial regions of the noninfarcted left ventricular wall and action potentials were recorded using whole-cell patch clamp technique. Results Compared with sham group, the monophasic action potential duration （MAPD90） of three layers myocardium were all prolonged. Prolongation of MAPD90 of midmyocardial cell was the most striking and ventricular fibrillation threshold （VFT） was decreased. After treatment with imidapril, the transmural dispersion of repolarization （TDR） decreased and the VFT enhanced. Conclusion Imidapril reduced the transmural dispersion of repolarization of noninfarcted area in rabbits after myocardial infarction, which may contribute to its antiarrhythmic efficacy.

关 键 词：咪达普利 心肌梗死 动作电位 复极不均一性 兔 

分 类 号：R965[医药卫生—药理学] R972.2[医药卫生—药学]