马桑内酯对大鼠海马神经元钠电流的影响

目的 研究马桑内酯(coriaria lactone,CL)对大鼠海马神经元钠离子通道电流的影响,探讨该影响在CL致痫中的意义.方法 利用全细胞膜片钳技术,在急性分离的大鼠海马神经元上记录钠电流,观察CL对电流幅度的影响.结果 经0.1 mg/mL、0.2 mg/mL的CL作用后,海马神经元钠电流有不同程度的增加CL 0.1 mg/mL组的最大峰值电流密度为(-90.11±14.02) pA/pF,增幅为17.32%±8.52%;CL 0.2 mg/mL组的最大峰值电流密度为(-111.52±6.65) pA/pF,增幅为37.98%±4.91%];经与对照组相比,CL 0.2 mg/mL组(P＜0.05)的变化较CL 0.1 mg/mL组(P＞0.05)明显.结论 CL使海马神经元电压依赖性钠电流的幅度增大,从而改变细胞的兴奋性,引发异常放电.

Effects of Coriaria Lactone on the Sodium Currents of Actuely Isolated Rat Hippocampal Neurons

OBJECTIVE: The present study tried to find out the effects of coriaria lactone (CL) on the sodium currents of the rat hippocampal neurons and their significance. METHODS: The sodium currents of the acutely isolated Sprague-Dawley rat hippocampal neurons were recorded by employing the patch-clamp technique in the whole-cell voltage-clamp mode. The effects of CL on the peak currents in the neuron membrane were assessed and analyzed. RESULTS: Both 0.1 mg/mL and 0.2 mg/mL CL increased the maximal peak density of sodium currents significantly (17.32%+/-8.52% vs 37.98%+/-4.91%). The effect of 0.2 mg/mL CL (P < 0.05) was more significant than that of 0.1 mg/mL CL (P > 0.05), when compared with the control (3.16%+/-0.65%). CONCLUSION: CL can increase the amplitudes of the voltage-dependent sodium currents in the acutely isolated hippocampal neurons. This effect may contribute to the enhanced excitability of hippocampal neurons and play a role in the epileptogenetic process of CL.