3, 5, 4'-三甲基白藜芦醇对豚鼠心室肌细胞钠电流和钾电流的影响

Effects of 3,5,4'-Trimethoxystilbene on Sodium and Potassium Current in Guinea Pig Ventricular Myocytes

关键词:  3, 5, 4'-三甲基白藜芦醇  心室肌细胞  钠电流  钾电流

Key words:  3, 5, 4'-trimethoxystilbene  ventricular myocytes  sodium current  potassium current

摘要:

目的 研究3, 5, 4'-三甲基白藜芦醇(trans-resveratrol derivative 3,5,4'-trimethoxystilbene，TMS)对豚鼠心室肌细胞钠电流(I_Na)和钾电流(I_K1)的直接作用，探讨其心肌保护作用。方法 用全细胞膜片钳技术记录TMS对单个心室肌细胞I_Na和I_K1的作用。结果 TMS(10 μmol·L^-1)可快速抑制豚鼠心室肌细胞I_Na，用药后3 min左右即开始起效，10 min时抑制率为(36.8±5.6)％(P<0.005)，洗脱后可完全恢复；1，3 μmol·L^-1 TMS未影响I_Na大小。TMS不改变I_Na的最大激活电压，也不影响I_K1的大小。10 μmol·L^-1使半数最大失活电压(V_1/2)由(-87.0±3.3)mV变化到(-96.7±3.5)mV (P<0.001)，使失活曲线斜率(S)由(4.9±0.3)mV 变化到(5.4±0.3)mV (P<0.01)；使半数最大激活电压(V_1/2) (-38.9±1.4)mV 变化到(-47.3±1.3)mV (P<0.001)，未改变激活S。结论 TMS可直接作用于豚鼠心室肌细胞，快速抑制I_Na，且此作用快速、可逆。

Abstract:

OBJECTIVE To investigate the effects of trans-resveratrol derivative 3,5,4'-trimethoxystilbene(TMS) on sodium current(I_Na) and potassium current(I_K1) in guinea pig ventricular myocytes, and to investigate the mechanism of cardioprotection. METHODS Single cardiac myocytes were isolated by enzyme, and the effect were assessed by applying whole-cell patch clamp technique. RESULTS TMS(10 μmol·L^-1) was shown to inhibit I_Na of guinea pig ventricular myocytes and acted quickly (about 3 min), and the inhibition ratio was (36.8±5.6)％(P<0.005) in 10 mins, and its effects were reversible completely after a 10 min washout. 1, 3 μmol·L^-1 TMS didn't decrease I_Na. The maximal activating voltage of INa and I_K1 were not changed. For availability, V_1/2 and S were (-87.0±3.3)mV and (4.9±0.3)mV for control and (-96.7±3.5)mV (P<0.001) and (5.4±0.3)mV (P<0.01) in 10 μmol·L^-1 TMS. For activation, V_1/2 were (-38.9±1.4)mV for control and (-47.3±1.3)mV(P<0.001) in 10 μmol·L^-1 TMS, S could not be changed. CONCLUSION TMS can exhibit direct inhibitory effects on I_Na in guinea pig ventricular myocytes, and these effects were reversible completely.