人参单体Rg_2对钙通道作用的单通道分析及电子自旋共振谱研究

Study of Ginseng Monomer Rg_2 on Calcium Channel and Electronic Spin Resonance Spectra

在 Wistar 大鼠乳鼠心室肌单个细胞上,用连细胞电压钳法,观察人参三醇组皂甙单体 Rg_2 60μmol/L 对钙通道单通道活动的影响,并与钙通道阻滞剂异博定79μmol/L、钙通道激动剂 Bay K 8644 5μmol/L 对照,证明 Rg_2对钙通道有阻滞作用,其机制在于使钙通道的开放时间缩短、开放概率减少、关闭时间延长,而对 Ba^(2+)流幅值无明显影响。用电子自旋共振法(ESR)测定了培养心肌细胞的自由基含量,Rg_230μmol/L 能显著抑制黄嘌吟0.42nmol/L、黄嘌呤氧化酶5.3nmol/L 所致的自由基含量的增多。

The influence of panaxitriol saponin monomer Rg_2 60μmol/L on single calcium channel activity from cul- tured neonatal Wistar rat myocardial cells was observed using the cell-attached configuration of patch clamp tech- nique,compared with that of calcium channel blocker verapamil 79μmol/L and calcium channel activator BAY K8644 5μmol/L.The inhibiting effects of Rg_2 on the three types of calcium channel were observed.The mecha- nism was that Rg_2 shortened the open time,decreased the open-state probability,extended the close time of cal- cium channels,without influencing the amplitude of the ionic current flowing through the opening calcium chan- nel.The free radical amount of the cultured myocardial cells was measured by using electronic spin resonance (ESR)method.Rg_2 30μmol/L could inhibit the increase in free radical amount induced by xanthine 0.42 mmol/ L and xanthine-oxidase 5.3nmol/L.