三七总皂甙对豚鼠心房肌细胞电生理特性的影响

目的： 研究三七总皂甙(panax notoginseng saponins,PNS)对离体豚鼠左心耳心肌细胞(left atrial appendage,LAA)电生理特性的影响, 以探讨其抗心律失常的作用机制。方法：应用标准玻璃微电极细胞内记录技术，记录不同浓度PNS灌流时，离体豚鼠左心耳心肌细胞的动作电位(action potential,AP)和有效不应期(effective refractory period,ERP)。结果：0.7、7、70、700 mg/L PNS在灌流20 min时作用最突出，与对照组比较7 mg/L PNS灌流20 min时的动作电位时程(action potential duration, APD) APD80，70 mg/L灌流20、30、40 min时APD50和APD80均明显延长（P<0.05）。0.7-700 mg/L 4个浓度组的PNS灌流20min时豚鼠心房肌细胞的静息电位(rest potential，RP)、动作电位幅度(action potential amplitude，APA) 和0相最大除极速率(Vmax)无明显变化。7 mg/L和70 mg/L的PNS灌流20min能明显延长心房肌细胞的ERP，与对照组比较由（127.00±7.26）ms分别延长为（153.00±9.19）ms和(161.00±10.21)ms,P<0.01。而在7 000 mg/L高浓度时，灌流10 min以后即出现心律失常现象。结论：一定浓度的PNS能延长豚鼠心房肌细胞的APD和ERP，与胺碘酮(amiodarone)相似，这可能是其抗心律失常的作用机制。

Effect of panax notoginseng saponins on electrophysiological characteristic of atrial cardiomyocytes in guinea pig

AIM: To study the effect of panax notoginseng saponins on the left atrial appendage (LAA) of the guinea pigs. METHODS: Standard microelectrode intracellular recording technique was used to record the LAA action potential (AP) and the effective refractory period (ERP) in the guinea pigs during the pouring with different density of PNS. RESULTS: The effect of PNS in concentration of 0.7, 7, 70, 700 mg/L was significant at 20 min, the APD50 and APD80 of the pouring at 20 min, 30 min, 40 min of the 70 mg/L was longer than the reference group (P<0.05). The rest potential (RP), action potential amplitude (APA) and Vmax kept no change during the pouring at 20 min with 4 difference densities from 0.7 to 700 mg/L. The pouring at 20 min of 7 mg/L and 70 mg/L obviously prolonged the ERP of the atrial cardiomyocytes. compared to the reference group, it prolonged from (127.00±7.26) ms to (153.00±9.19) ms and (161.00±10.21) ms (P<0.01). However, pouring at 10 min with 7 000 mg/L caused the arrhythmias. CONCLUSION: PNS prolongs the APD and ERP in guinea pig atrial cardiomyocytes. It may be the mechanism of PNS against arrhythmias in cellular level, which is similar to amiodarone.