论文部分内容阅读
目的 研究辣椒素对人心房肌的电生理效应及其作用机制。方法 应用经典玻璃微电极方法记录人心房肌特殊细胞的动作电位。结果 辣椒素(1～ 30 μmol·L- 1)浓度依赖性地抑制人心房肌纤维的动作电位幅值 ,0期最大除极速率 ,舒张期 (4相 )除极化速率和起搏细胞放电频率 ,此外还缩短 90 %动作电位时程。应用L 型钙通道开放剂BayK86 44(0 .5 μmol·L- 1)可拮抗辣椒素对人心房肌纤维的上述电生理效应 ,但辣椒素受体竞争性抑制剂cap sazepine(10 μmol·L- 1)对辣椒素的效应并无影响。结论 辣椒素对人心房肌具有负性变时作用 ,并可缩短复极化时程。这些效应可能与其抑制钙离子内流有关。
Objective To study the electrophysiological effects of capsaicin on human atrial myocardium and its mechanism of action. Methods The classic glass microelectrode method was used to record the action potentials of human atrial myocytes. Results Capsaicin (1-30 μmol·L-1) inhibited the action potential amplitude of human atrial fibers in a concentration-dependent manner, and the maximum depolarization rate in phase 0, diastolic phase (4 phase) in addition to the polarization rate and firing frequency of the pacemaker cells. In addition, the 90% action potential duration is also shortened. L-type calcium channel opener BayK86 44 (0.5 μmol·L-1) could antagonize the above electrophysiological effects of capsaicin on human atrial myofibers, but capsaicin receptor competitive inhibitor cap sazepine (10 μmol·L- 1) No effect on the effect of capsaicin. Conclusion Capsaicin has a negative chronotropic effect on human atrial muscles and shortens the repolarization time course. These effects may be related to their inhibition of calcium influx.