六甲氧苄嗪抗缺血再灌注性心律失常与氧自由基的关系

Relationship between Hexametazidine Reperfusioninduced Arrhythmias and Free Oxygen Radical

目的：研究六甲氧苄嗪（ＨＭＺ）对再灌注性心律失常的影响，同时探讨与氧自由基的关系。方法：用离体兔心灌注和ＳＤ大鼠在体心脏冠状动脉结扎，制造心肌缺血后再灌注两种模型。结果：ＨＭＺ４ｍｇ／ｋｇ和灌流浓度１６μｍｏｌ／Ｌ能使心律失常的发生率明显降低，并能提高红细胞内ＳＯＤ的活力，血浆脂质过氧化代谢产物ＭＤＡ含量由对照组的２．６±０．４ｎｍｏｌ／Ｌ减少到１．８±０．２ｎｍｏｌ／Ｌ。实验观察到具有剂量依赖性的负性频率作用。结论：ＨＭＺ具有较好的抗心律失常药理效应，其机理可能与降低心率和抑制自由基反应有关。

Objective: To investigate the effect of hexametazidine (HMZ) on reperfusioninduced arrhythmias (RA) after ischemia and the relationship to free oxygen radical. Methods: Myocardial ischemic and reperfusion isolated heart model was established by temporary occlusion of the coronary artery of SD rats. Results: The motality of RA was decreased significantly. Superoxide dismurase (SOD) activity of the red blood cell increased and plasma malondialdehyde level decreased when HMZ (16μmol/L,4mg/kg) was given iv. The negative chronotropic action of HMZ was dosedependent. Conclusion: HMZ can inhibit reperfusioninduced arrhythmias after ischemia. The mechanism may be related to its inhibiting effect on HR and response to free oxygen radical.