电刺激小脑外侧核对内皮素-1诱导运动皮层缺血大鼠模型局部场电位的影响

Protective Effects of Deep Electrical Stimulation of the Lateral Cerebellar Nucleus on the Cortical Local Field Potential in a Rat Model of Focal Cerebral Ischemia Induced by Endothelin-1

目的研究电刺激小脑外侧核(LCN)对内皮素-1(ET-1)诱导局灶性脑缺血大鼠模型的局部场电位(LFP)的影响。方法ET-1定点注射诱导大鼠运动皮层局灶性缺血模型,造模后休息1周,安上自制刺激电极和记录电极。刺激组给予30 HZ脑深部电刺激(DBS),每天8 h,连续14 d。采用电生理记录系统分析LCN DBS前以及DBS 14 d后的前肢刺激诱发LFP。结果ET-1诱导局灶性缺血后,患侧皮层的电生理活动显著低于健侧(P<0.001)。给予电刺激治疗后能显著提高患侧皮层诱发的LFP(P<0.001),但与健侧比仍有明显差异(P<0.01)。同时,分析不同波段LFP的数据结果显示,与电刺激前相比,电刺激后Theta波(P<0.01)、Alpha波(P<0.05)以及Beta-1波(P<0.01)患侧/健侧LFP功率的比值均显著升高。结论ET-1定点注射诱导局灶性脑缺血后,局部场电位降低,皮层神经元活动减弱,而LCN DBS对皮层神经元的兴奋性有改善作用。

Objective This article aims to investigate the effect of electrical stimulation of the lateral cerebellar nucleus on the LFP in rats with focal cerebral ischemia induced by ET-1.Method Healthy adult male SD rats were injected with ET-1 into the motor cortex to induce a model of focal cerebral ischemia.After 1 week of recovery,rats were installed with self-made stimulation electrode and recording electrode.Then electrical stimulation of 30 HZ were performed for 8 hours per day for 14 consecutive days.Local field potentials evoked during forepaw stimulation were recorded by electrophysiological recorderto analyzed evoked activity of motor cortex.Result After focal ischemia induced by ET-1,the evoked acticivty of the ischemic cortex was significantly reduced,compared with that of the contralateral cortex(P<0.001).The induced LFP of the ischemic cortex was significantly increased after electrical stimulation(P<0.001),but still lower than that of the contralateral cortex(P<0.01).The result of LFP in all frequency bands showed that the average inter-hemispheric power ratio were increased in Theta band(P<0.01),Alpha band(P<0.05) and beta-1 band(P<0.01) after DBS for 14 days.Conclusion After ET-1-induced cortical ischemia,average power in LTP was reduced,indicating the decrease of cortical activity,while LCN DBS could improve the excitability of cortical neurons.