黄芩苷对海马神经元Na^+、K^+及Ca^2+电流调控作用的研究

Effect of baicalin on current regulation of Na^+,K^+and Ca^2+in hippocampal neurons

目的探讨黄芩苷对电压门控钠通道、钾通道及钙通道的选择性调控作用,为临床应用提供实验依据。方法急性分离大鼠海马神经元,利用全细胞膜片钳技术研究黄芩苷对海马神经元内向钠电流、瞬时外向钾电流、延迟整流钾电流和钙电流的影响。结果(1)在钠电流检测外液中加入钠通道抑制剂TTX后,内向钠电流几乎完全被抑制;加入10μM黄芩苷后,可显著抑制钠电流(P<0.01);(2)在钾电流检测外液中加入钾通道抑制剂TEA后,延迟整流钾电流大部分被抑制(P<0.01),瞬时外向钾电流无明显变化;加入10μM黄芩苷后,迟整流钾电流部分被抑制(P<0.05),瞬时外向钾电流无明显变化;(3)在钙电流检测外液中加入钙通道抑制剂Nifedipine后,钙电流被明显抑制(P<0.01);加入10μM黄芩苷后,钙电流无明显变化。结论黄芩苷对电压门控钠电流及延迟整流钾电流具有选择性抑制作用。

Objective To explore the selective regulation effect of baicalin on voltage gated sodium channel,potassium channel and calcium channel.Methods The hippocampal neurons were separated acutely.Then the effects of baicalin on inward sodium current,instantaneous outward potassium current,delayed rectifying potassium current and calcium current in hippocampal neu-rons were studied by whole-cell patch clamp technique.Results(1)After sodium channel inhibitor TTX was added to the so-dium current detection solution,the inward sodium current was almost completely inhibited;when 10μM baicalin was added,the current was significantly inhibited(P<0.01);(2)After potassium channel inhibitor TEA was added to the potassium current de-tection solution,the delayed rectifying potassium current was largely inhibited(P<0.01),and the instantaneous outward potassi-um current showed no significant change;when 10μM baicalin was added,the delayed rectifying potassium current was partly in-hibited(P<0.05),but the instantaneous outward potassium current showed no significant change;(3)After calcium channel in-hibitor Nifedipine was added to the calcium current detection solution,the calcium current was significantly inhibited(P<0.01);when 10μM baicalin was added,there's no change.Conclusion Baicalin has a selective inhibitory effect on voltage-gated so-dium current and delayed rectifying potassium current.