摘要
An ishemic ventricular tachyarrhythmias canine model was established in open-chest dogs subjected to programmed electrical stimulation (PES)for 5-8 days after acute myocardial infarction. The electrophysiologic effects of neferine (Nef) and procainamide (PA) were observed in this model. With routine methods of PES,ventricular tachycardia (VT)and ventricular fibrillation (VF) could be reproducibly initiated. Both drugs lengthened the QTc interval (P【0.01) and effective refractory period(ERP)of normal and ischemic ventricular myocardia (NERP and IERP) respectively (P【0.01), decreased the dispersion of ERP in ischemic myocardium and the dispersion of ERP in left ventricle (P【0.01), and increased the diastolic excitability threshold of normal and ischemic ventricular myocardia (P【0.01). The two compounds prevented the PES-induced VT or VF (Nef group P【0.01, PA group P【0.05) and ischemia-induced VF (P【0.05). The results indicated that neferine and procainamide may be effective in preventing the onset of reentrant ventricular tachyarrhythmias after myocardial ischemic damage in dogs.
用冠脉Harris二期结扎并部分再灌注及吻合支缝扎法造成犬急性前壁心肌梗塞 ,5 - 8天后辅以心室程控刺激技术 (PES)进行心电生理检查及复制快速室性心律失常 ,观察甲基莲心碱 (Neferine)抗心律失常的电生理作用并与普鲁卡因胺(PA)对比。结果表明 ,Neferine可显著延长QTc间期 (P <0 0 1)及正常心肌和缺血心肌的有效不应期 (NERP及IERP) (P <0 0 1) ,提高正常心肌和缺血心肌舒张期兴奋阈值 (NET及IET) (P <0 0 1) ,缩小缺血心肌和左室心肌ERP离散度 (IDR和VDR) (P <0 0 1) ,抑制心室PES诱发的持续性室速 (SVT)或室颤 (VF) (P <0 0 1) ,并能有效地预防犬慢性心肌梗塞后再次缺血所致的自发性VF (P <0 0 5 ) ,表明Neferine有抗缺血性快速室性心律失常的作用 。
