ABSTRACT
Objective:To observe and analyze the changes in activity of layer 2/3 cortical neurons in isoflurane-anesthetized mice by Real-time Ultra-large-Scale High-resolution (RUSH) imaging platform.Methods:Clean-grade healthy male Rasgrf2-Cre/Ai148d mice, aged 8-12 weeks, weighing 18-25 g, were studied.The mice recovered ten days after the skull replacement surgery and proceeded to the next experiment.Imaging data of calcium fluorescence signals from layer 2/3 cortical neurons were acquired by RUSH imaging platform after fixing the head of mice.The time of imaging data acquisition in the awake state, during anesthesia with 1.2% isoflurane, and after the end of anesthesia was 100, 600 and 600 s, respectively.Imaging data were analyzed using Image J and MATLAB softwares.Results:The overall trend of activity of layer 2/3 cortical neurons decreased first and then stabilized with the inhalation of 1.2% isoflurane.The cortical neural activity were gradually increased when isoflurane inhalation was stopped.The recovery rate of neural activity was different in different brain regions after isoflurane inhalation was stopped.The recovery of neural activity in the primary motor cortex was delayed obviously.During the maintenance of anesthesia, the activities of most layer 2/3 cortical neurons in the retrosplenial cortex were weakened, however, some of the neurons became more active.Conclusions:The neural activity in the 2/3 layer of cortex in isoflurane anesthetized mice is inconsistent in observation region, brain region and single cell, suggesting that different neural pathways are involved in the process of anesthesia induction and recovery from anesthesia.