Yurek D M, Randall P K
Division of Neurosurgery, University of Kentucky Medical Center, Lexington 40536.
J Neurosci Methods. 1991 Mar;37(1):81-91. doi: 10.1016/0165-0270(91)90023-s.
This paper demonstrates a technique for measuring depth electroencephalographic (EEG) recordings from the freely moving mouse. This technique minimizes electrical artifact associated with gross movements by amplifying the current of the EEG signal directly at permanently indwelling electrodes. Stable EEG signals, with high signal-to-noise ratios, can be obtained from these animals while their movement inside the testing cage remains relatively unrestricted. We used this technique to examine the effects of dopamine (DA) receptor agonist and antagonist treatments on depth EEG signals generated within the striatum. Baseline measures of spontaneous striatal EEG activity were obtained prior to drug administration and post-drug measures of striatal activity were subsequently obtained. Apomorphine treatment resulted in desynchronization of striatal EEG signals while haloperidol or sulpiride treatment induced slow wave synchronization. Fast Fourier analysis of EEG signals revealed that DA agonist and antagonist treatment altered spontaneous striatal EEG activity in an opposite manner--relative to baseline signals, apomorphine attenuated low frequency components and augmented higher frequency components of the signal while haloperidol augmented low frequency components and attenuated higher frequency components of the signal. Moreover, mice pretreated with unilateral intracerebral injections of sulpiride and subsequently administered systemic apomorphine simultaneously demonstrated EEG synchronization on the side ipsilateral to the injection of sulpiride and EEG desynchronization on the contralateral side. The population of neurons examined in the medial striatum appear to have the properties of being excitatory to DA agonist stimulation and show decreased activity following DA antagonist treatment. These results suggest that striatal EEG activity may be used as measure of postsynaptic activity of dopaminergic neurons.
本文展示了一种用于测量自由活动小鼠深度脑电图（EEG）记录的技术。该技术通过在永久植入的电极处直接放大EEG信号的电流，将与大幅度运动相关的电伪迹降至最低。在这些动物的测试笼内运动相对不受限制的情况下，可以从它们身上获得具有高信噪比的稳定EEG信号。我们使用该技术研究多巴胺（DA）受体激动剂和拮抗剂处理对纹状体内产生的深度EEG信号的影响。在给药前获得纹状体EEG自发活动的基线测量值，随后获得给药后纹状体活动的测量值。阿扑吗啡处理导致纹状体EEG信号去同步化，而氟哌啶醇或舒必利处理诱导慢波同步化。EEG信号的快速傅里叶分析表明，DA激动剂和拮抗剂处理以相反的方式改变了纹状体EEG自发活动——相对于基线信号，阿扑吗啡减弱了信号的低频成分并增强了高频成分，而氟哌啶醇增强了信号的低频成分并减弱了高频成分。此外，预先经单侧脑内注射舒必利处理并随后同时给予全身阿扑吗啡的小鼠，在注射舒必利的同侧表现出EEG同步化，而在对侧表现出EEG去同步化。在内侧纹状体中检查的神经元群体似乎具有对DA激动剂刺激产生兴奋的特性，并且在DA拮抗剂处理后活性降低。这些结果表明，纹状体EEG活动可用作多巴胺能神经元突触后活动的指标。
