龙血素B对三叉神经节河豚毒素不敏感型钠通道电流的调制作用

Modulatory Effects of Loureirin B on Tetrodotoxin-resistance Voltage-Gated Sodium Currents in Trigeminal Ganglion Neurons

目的研究血竭重要成分龙血素B对小鼠三叉神经节河豚毒素不敏感(TTX-R)钠电流的作用。方法采用酶解法分离小鼠三叉神经节细胞,应用全细胞膜片钳技术,观察龙血素B对单个三叉神经节(trigem inal ganglion TG)细胞TTX-R钠电流幅值的影响。结果龙血素B对TTX-R钠电流呈浓度依赖性抑制,且抑制作用可逆;高浓度的龙血素B(0.2mmol/L)加速TTX-R钠通道电流的失活过程,延迟其复活过程,对激活过程无显著影响。结论龙血素B显著抑制TTX-R钠电流,且这种抑制作用发生在钠通道的失活过程而非激活过程,这种作用可能是其镇痛作用的机理之一。

Objective The purpose is to search out the effective element of Loureirin B on tetrodotoxin-resistance（TTX-R） voltage-gated sodium current（VGSC） in trigeminal （TG） neurons. Methods The TG neurons were enzymatically isolated from mice, and then the effect of Loureirin B on the TTX-R VGSC was assessed using whole-cell patch-clamp technology. Results Loureirin B inhibits the TTX-R peak sodium currents in a close -dependent model and the inhibition is reversible. 0.2mmol/L loureirin B accelerates the inactive process of the TTX-R sodium currents and delays the revivable process but does not affect the activitive process. Conclusion Loureirin B significantly inhibits the TTX-R sodium currents and perhaps the inhibition is one of the ease pain mechanism of Loureirin B.