基于双模检测仪器的大鼠神经放电和神经化学信号同步检测研究

研制了一种可同步检测神经电生理和化学信号的双模检测仪，并应用此仪器开展了双模同步检测实验。此仪器具有0.3μV电压分辨率的64通道神经电生理检测功能、pA级电流精度的4通道电化学检测功能，具备动作电位分离分类、计时电流法、循环伏安法等常用的检测功能，并且能实现对双模神经信号的同步观测和分析。在采用此仪器开展的单模实验中，完整地检测到了64通道的模拟神经信号，结合微电极阵列获得了信噪比( S/N)为6的神经动作电位发放；采用循环伏安法，获得了铁氰化钾在溶液浓度0.1~10 mmol/L范围内与电流响应的线性相关系数为0.9889；同时，采用计时电流法获得了抗坏血酸在溶液浓度10~800μmol/L 范围内与电流响应的线性相关系数为0.9841。结合大鼠脑缺血模型开展了双模检测实验，在该模型中成功地同步检测到了神经动作电位发放和抗坏血酸浓度变化引起的电流变化，并发现大鼠大脑初级感觉皮层抗坏血酸浓度与动作电位发放呈一定负相关关系。

Synchronous Detection of Rat Neural Spike Firing and Neurochemical Signals Based on Dual-mode Recording Instrument

A dual-mode recording system used for synchronous detection of neuroeletrical and neurochemical signals was developed, and a dual-mode synchronous detection experiment was carried out using the instrument. The device comprised 64-channel neuroelectricity recording module with voltage resolution of 0. 3 μV and 4-channel neurochemistry recording module with current resolution of 1 pA. The software had many basic features, including Spike separation and sort, chronoamperometry, cyclic voltammetry, etc. In particular, the software could observe and analyze the dual-mode neural signals synchronously. The performance of the system was demonstrated in the single mode detection experiments. In neuroeletrical experiments, 64-channel simulate neural signals were detected and the signal to noise ratio ( S/N) of Spike recorded from cortex of Sprague-Dawley ( SD ) rat was 6. In the K3 Fe ( CN )6 ] and ascorbic acid measurement experiments, the current response of K3 Fe ( CN)6 ] in the range of 0. 1-10 mmol/L was obtained by cyclic voltammetry, with a correlation coefficient of 0. 9889, and the current response of ascorbic acid ( concentration:10-800 μmol/L) by chronoamperometry increased linearly with a correlation coefficient of 0. 9841. Based on the rat model of global cerebral ischemia, a dual-mode detection experiment was carried out. In the experiment, the neuroelectrical and neurochemical signals were synchronously recorded in the SD rat primary visual cortex. According to the experimental results, we got the conclusion that the concentration of ascorbic acid negatively related to the Spike firing in the SD rat primary visual cortex.