Effect of desflurane on activity of neurons in 2/3 layer cortex of mice based on high-resolution light-field intelligent imaging system / 中华麻醉学杂志

ABSTRACT

Objective:To explore the effect of desflurane on activity of neurons in 2/3 layer cortex of mice by using high-resolution light-field intelligent imaging system.Methods:Six SPF healthy male Rasgrf/Ai148d mice, aged 8-12 weeks, weighing 25-30 g, were selected. The 6 mice were subjected to skull replacement surgery and then recovered for 2 weeks before experiment.The mice were first fixed under the high-resolution light-field intelligent imaging system for 5 min before calcium signals in 2/3 layer cortex were recorded. The 7.5% desflurane was inhaled for anesthesia starting from 100 s of recording and inhalation was stopped at 700 s, and then the recording continued for 700 s. The total duration of the experiment was 1 500 s. Neurons were extracted and data were analyzed using MATLAB software.Results:When mice were subjected to inhalation anesthesia with desflurane, the calcium fluorescence intensity and percentage of active neurons in the cortex 2/3 layers initially increased significantly, then continuously declined, stabilizing after about 100 s of inhalation. After cessation of inhalation, it gradually recovered to the pre-anesthetic level around 50 s post-inhalation. During the induction period of anesthesia, the percentage of active neurons was significantly higher in the retrosplenial cortex than in the other brain regions ( P<0.05). Conclusions:The disappearance and recovery of consciousness induced by desflurane anesthesia at the neuronal level is not a " symmetrical" process. Neuronal activity in the brain exhibits asymmetry when entering and recovering from an anesthetized state. The retrosplenial cortex, which is related to sleep-wake cycles, may play a crucial role in maintaining consciousness during induction of anesthesia with desflurane.