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

Abstract

Abstract 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 this instrument. The device comprised a 64-channel neuroelectricity recording module with voltage resolution of 0.3 μV and a 4-channel neurochemistry recording module with current resolution of 1 pA. The software had many basic detection features as 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 K 3 [Fe(CN) 6 ] and ascorbic acid measurement experiments, the current response of K 3 [Fe(CN) 6 ] in the range of 0.1−10 mM was obtained by cyclic voltammetry, with a correlation coefficient of 0.9889, and the current response of ascorbic acid (10 − 800 µM) 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.