外源性锌离子对大鼠海马切片癫痫样放电的起源、传播与频率特性的调节作用

本研究采用多电极记录技术,在离体条件下研究外源性锌离子(Zn2+)对无镁人工脑脊液诱导的Sprague-Dawley大鼠海马切片癫痫样放电的起源、传播与频率特性的调节作用。结果表明:1μmol/L和100μmol/L的Zn2+作用于海马切片,不改变海马切片上癫痫样放电的起始位置,但能够降低癫痫样放电顺行和逆行两个方向的传播速度,并改变癫痫样放电不同频率范围成分所占的比例。以上结果提示,1μmol/L和100μmol/L的Zn2+可以对海马切片上的癫痫样放电起到调节作用,减慢癫痫样放电在网络中的传播速度,同时,可能对神经元放电活动起到去同步化的作用。

The Modulatory Effects of Exogenous Zn2+ on Propagation and Frequency of Epileptiform Discharges on Rat Hippocampal Slices

The modulatory effects of exogenous Zn2+ on initiation,propagation and frequency characteristics of epileptiform discharges induced by Mg2+-free artificial cerebrospinal fluid(ACSF) in hippocampal slices of Sprague-Dawley rats were examined by multi-electrode array(MEA) system.The main results of the present study are: the modulatory effects of 1 μmol/L and 100 μmol/L Zn2+ did not change the initiation site of the epileptiform discharges,but the antegrade and retrograde speed of epileptiform discharges were slowed down by perfusion of Zn2+,and the ratio of different frequency components were changed by Zn2+ application.These results imply that 1 μmol/L and 100 μmol/L Zn2+ play the neuromodulatory effects on epileptiform discharges in hippocampal slices,which can slow down the propagation speeds of epileptiform discharges in the network.Zn2+ may also play the desynchronization effects on the neural firing activity.