心肌肽素抗心律失常作用及对钙和钾离子通道的影响

Effect of cardiomyopeptidin against arrhythmia and influence on calcium and potassium ion channel

目的 :观察心肌肽素对室速、室颤发生率及心室肌细胞钙、钾电流的影响。方法 :建立整体动物心肌缺血 -再灌流损伤模型。以膜片钳技术记录单个心室肌细胞内向钙电流及电流 -电压曲线、内向整流钾电流及延迟整流钾电流。结果 :心肌肽素可降低室速、室颤发生率 ,在一定浓度下对心肌细胞内向钙电流有明显的抑制作用 ,且该作用具有一定的电压依赖性 ,而对内向整流钾电流及延迟整流钾电流均无作用。结论 :心肌肽素能降低缺血 -再灌流损伤大鼠严重室性心律失常的发生率 。

AIM: To observe the effect of cardiomyopeptidin (CMP) on incidence rate of ventricular tachycardia(VT) and ventricular fibrillation(VF)and the influence of CMP on the inward calcium current and potassium current. METHODS: The ischemia-reperfusion model were developed in rat heart in vivo . The influence of CMP on the inward calcium current(I Ca ) and its current-voltage relationship,the inward rectifier and delayed rectifier potassium current were recorded by patch-clamp techniques in guinea pig ventricular myocytes. RESULTS: The results showed that CMP could decrease the incidence rate of VT and VF, and could inhibited the inward calcium current of myocardial cells in certain concentration range and in a voltage-dependent manner. But CMP had no effect on both of inward rectifier and delayed rectifier potassium current. CONCLUSION: CMP could decrease the incidence rate of serious ventricular arrhythmia in rat heart injured by ischemia-reperfusion,this may be related to its decreasing I Ca in ventricular myocytes.