葛根素对慢性偏头痛小鼠三叉神经节细胞钠离子电流及动作电位的影响

Effect of puerarin on sodium ion current and action potential in trigeminal ganglion cells of mice with chronic migraine

目的通过观察葛根素对硝酸甘油诱导的慢性偏头痛模型小鼠行为学、三叉神经节细胞钠离子电流抑制率和动作电位的影响,探讨其治疗慢性偏头痛的作用机制。方法随机取6只雄性C57BL/6小鼠,处死后分离三叉神经节细胞,检测不同浓度的葛根素对电压依赖性钠离子通道电流的抑制率。建立硝酸甘油诱导的慢性偏头痛小鼠模型,给予药物干预后,qRT-PCR检测三叉神经节细胞神经元电压门控钠通道基因(voltage-gated sodium channelα1-subunit gene,SCN1A)m RNA表达;用膜片钳记录各组小鼠三叉神经节细胞的动作电位参数。结果葛根素对正常小鼠三叉神经节细胞的电压门控性钠离子通道抑制率的半数抑制浓度(half inhibitory concentration,IC50)为29.96μmol/L。与对照组比较,模型组小鼠0~30、30~60、60~90、90~120 min各时间段抓头次数及2 h内抓头次数总和显著增加(P<0.05、0.001),三叉神经节细胞中SCN1A m RNA表达显著升高(P<0.001),动作电位发放频率和静息膜电位显著升高(P<0.001)。与模型组比较,葛根素(50、100、200 mg/kg)组30~60 min抓头次数和2 h内抓头次数总和显著减少(P<0.05、0.01),葛根素(200 mg/kg)组90~120 min抓头次数显著减少(P<0.001);葛根素(100、200 mg/kg)组小鼠三叉神经节细胞中SCN1A m RNA表达显著降低(P<0.001);葛根素(50、100、200 mg/kg)组小鼠三叉神经节细胞动作电位发放频率和静息膜电位显著下降(P<0.001)。结论葛根素通过阻断三叉神经节细胞钠离子电流和SCN1A mRNA表达,降低动作电位静息膜电位和发放频率,减少慢性偏头痛发作,有望成为临床治疗慢性偏头痛的辅助治疗药物。

Objective To explore the mechanism of puerarin on chronic migraine by observing the effects of puerarin on the behavior,sodium ion current inhibition rate,and action potential of trigeminal ganglion cells in nitroglycerin-induced chronic migraine model mice.Methods Six male C57BL/6 mice were randomly selected,and trigeminal ganglion cells were isolated after euthanasia.The inhibitory rate of different concentrations of puerarin on voltage dependent sodium ion channel currents were measured.A chronic migraine mouse model induced by nitroglycerin was established,and after drug intervention,qRT-PCR was used to detect the mRNA expression of voltage-gated sodium channel α1-subunit gene(SCN1A)in trigeminal ganglion cells;The action potential parameters of trigeminal ganglion cells in each group of mice was recorded using patch clamps.Results The half inhibitory concentration(IC50)of puerarin on voltage-gated sodium channel inhibition in normal mouse trigeminal ganglion cells was 29.96μmol/L.Compared with control group,mice in model group showed a significant increase in the number of head grabbing times at each time period of 0-30,30-60,60-90,90-120 min and the total number of head grabbing times within 2 h(P<0.05,0.001).The expression of SCN1A mRNA in trigeminal ganglion cells in model group was significantly increased(P<0.001),and the frequency of action potential firing and resting membrane potential were significantly increased(P<0.001).Compared with model group,puerarin(50,100,200 mg/kg)groups showed a significant decrease in the number of head grabbing times at 30-60 min and the total number of head grabbing times within 2 h(P<0.05,0.01),while puerarin(200 mg/kg)group showed a significant decrease in the number of head grabbing times at 90-120 min(P<0.001);The expression of SCN1A mRNA in trigeminal ganglion cells of mice in puerarin(100,200 mg/kg)groups was significantly reduced(P<0.001);The action potential firing frequency and resting membrane potential of trigeminal ganglion cells in mice treated with puerarin(50,100,200 mg/kg)were significantly decreased(P<0.001).Conclusion Puerarin could block the sodium ion current and SCN1A mRNA expression in trigeminal ganglion cells,reduce the resting membrane potential and firing frequency of action potentials,and reduce the onset of chronic migraine.It is expected to become an adjunctive therapeutic drug for clinical treatment of chronic migraine.