高频电刺激改变神经元发放与场电位节律之间的锁相关系  

High frequency stimulations change the phase-locking relationship between neuronal firing and the rhythms of field potentials

作　　者：马维健 封洲燕[1] 周文杰[1] 王兆祥[1] 蔡紫燕 

机构地区：[1]浙江大学生物医学工程与仪器科学学院生物医学工程教育部重点实验室,杭州310027

出　　处：《生物医学工程学杂志》2018年第1期1-7,共7页Journal of Biomedical Engineering

基　　金：国家自然科学基金资助项目(30970753)

摘　　要：临床上,已将深部脑刺激(DBS)技术成功应用于治疗多种脑部疾病。近年的研究推测,DBS技术使用的电脉冲高频刺激(HFS)可以改变神经元动作电位的病理性节律发放,这可能是DBS治疗脑部疾病的重要机制之一,但是这种推测尚需实验数据的证实。本文在已麻醉的大鼠海马CA1区的输入轴突束薛氏侧支(Schaffer collaterals)施加时长为1 min、频率为100 Hz的HFS,并分析刺激下游CA1区的锥体神经元和中间神经元的锋电位,考察两种神经元的节律性动作电位发放的变化情况。结果显示,麻醉大鼠CA1区的场电位存在明显的θ节律,且在顶树突层尤其明显,而神经元锋电位与θ节律存在锁相关系。与此基线记录相比较,在HFS期间,锥体神经元的锋电位与顶树突层θ节律的锁相值从0.36±0.12显著减小至0.06±0.04(P<0.001,配对t检验,N=8);中间神经元锋电位的锁相值也从0.27±0.08减小至0.09±0.05(P<0.01,配对t检验,N=8)。两类神经元与胞体层θ节律的锁相关系也有类似改变。此结果表明,对轴突束施加HFS可以消除下游神经元动作电位发放与场电位θ节律之间的锁相关系,改变神经元的节律性发放模式。这种现象产生的机制可能是HFS诱导的轴突传导障碍,此发现对于深入研究DBS的作用机制具有重要的意义。Deep brain stimulation （DBS） has been successfully used to treat a variety of brain diseases in clinic. Recent investigations have suggested that high frequency stimulation （HFS） of electrical pulses used by DBS might change pathological rhythms in action potential firing of neurons, which may be one of the important mechanisms of DBS therapy. However, experimental data are required to confirm the hypothesis. In the present study, 1 min of 100 Hz HFS was applied to the Schaffer collaterals of hippocampal CA 1 region in anaesthetized rats. The changes of the rhythmic firing of action potentials from pyramidal cells and interneurons were investigated in the downstream CA1 region. The results showed that obvious 0 rhythms were present in the field potential of CA1 region of the anesthetized rats. The θ rhythms were especially pronounced in the stratum radiatum. In addition, there was a phase-locking relationship between neuronal spikes and the O rhythms. However, HFS trains significantly decreased the phase-locking values between the spikes of pyramidal cells and the O rhythms in stratum radiatum from 0.36 ±0.12 to 0.06 ±0.04 （P 〈 0.001, paired t-test, N= 8）. The phase-locking values ofinterneuron spikes were also decreased significantly from 0.27 ±0.08 to 0.09 ±0.05 （P 〈 0.01, paired t-test, N = 8）. Similar changes were obtained in the phase-locking values between neuronal spikes and the O rhythms in the pyramidal layer. These results suggested that axonal HFS could eliminate the phase-locking relationship between action potentials of neurons and O rhythms thereby changing the rhythmic firing of downstream neurons. HFS induced conduction block in the axons might be one of the underlying mechanisms. The finding is important for further understanding the mechanisms of DBS.

关 键 词：高频电刺激 锋电位 节律性发放 Θ节律 锁相 

分 类 号：R741[医药卫生—神经病学与精神病学]