Shinohara H, Nishikado A, Wakatsuki T, Sakabe K, Ito S
Second Department of Internal Medicine, School of Medicine, University of Tokushima, Japan.
Jpn Heart J. 1998 May;39(3):363-73. doi: 10.1536/ihj.39.363.
This study was undertaken to clarify the effects of nicorandil on electrophysiological changes during acute ischemia and following reperfusion. We prepared an acute ischemic heart model by ligating the left anterior descending coronary artery in 27 dogs. After 10 minutes, reperfusion was performed. The changes in ventricular effective refractory period (ERP) and intramyocardial conduction time (ICT) were compared between the nicorandil group (n = 12) which received nicorandil intravenously before the coronary ligation and the control group (n = 15). In the control group, the ERP was shortened during ischemia, and rapidly shortened immediately after reperfusion, but was slightly prolonged 10 minutes after reperfusion. The ICT was prolonged during ischemia, but returned to the pre-ischemia value after reperfusion. In the nicorandil group, the changes in ERP and ICT were significantly inhibited compared to those in the control group. The incidence of ventricular fibrillation (VF) during reperfusion was 42% in the control group. However, there was no VF during reperfusion in the nicorandil group. Therefore, nicorandil may correct both the delayed conduction and the uneven ventricular effective refractory period detected during acute ischemia and following reperfusion, inhibiting the development of ventricular arrhythmia during reperfusion.
本研究旨在阐明尼可地尔对急性缺血及再灌注期间电生理变化的影响。我们通过结扎27只犬的左冠状动脉前降支制备急性缺血性心脏模型。10分钟后进行再灌注。比较了在冠状动脉结扎前静脉注射尼可地尔的尼可地尔组（n = 12）和对照组（n = 15）之间心室有效不应期（ERP）和心肌内传导时间（ICT）的变化。在对照组中，ERP在缺血期间缩短，再灌注后立即迅速缩短，但再灌注10分钟后略有延长。ICT在缺血期间延长，但再灌注后恢复到缺血前的值。与对照组相比，尼可地尔组中ERP和ICT的变化受到显著抑制。对照组再灌注期间室颤（VF）的发生率为42%。然而，尼可地尔组再灌注期间未发生室颤。因此，尼可地尔可能纠正急性缺血及再灌注期间检测到的延迟传导和心室有效不应期不均一性，抑制再灌注期间室性心律失常的发生。
