Objective To investigate the role of glutamatergic neurons in the basolateral amygdala(BLA)in regulating isoflurane anesthesia.Methods Healthy male Vglut2-Cre transgenic mice aged 8-12 weeks were used in the study.Fifteen mice were randomly divided into optogenetic activation group(ChR2 group),optogenetic inhibition group(GtACR group)and optogenetic control group(mCherry group),with 5 mice in each group.Excitatory optogenetic virus rAAV2/9-EF1α-DIO-hChR2-mCherry-WPRE-hGH pA,inhibitory optogenetic virus rAAV2/9-EF1 α-DIO-GtACR-mCherry-WPRE-hGH pA,and controlled virus rAAV2/9-EF1α-mCherry-WPRE-hGH pA were stereotaxically injected into BLA with embedded ceramic ferrules.After virus expression for 3 weeks,the test mice were anesthetized with 14 mL/L isoflurane,the cortical electroencephalography(EEG)of the mice was recorded,BLA glutamatergic neurons were optogenetically regulated during the stable time of burst-suppression ratio(BSR),and BSR was compared 2 min before and 2 min after light stimulation.Twenty-one Vglut2-Cre mice were randomly divided into chemogenetic activation group(hM3Dq group),chemogenetic inhibition group(hM4Di group)and chemogenetic control group(mCherry group),with 7 mice in each group.Chemogenetic regulation experiment was carried out 3 weeks after the chemogenetic virus was injected into bilateral BLA nuclei.The EEG spectrum and the percentage of total power of each frequency band were compared in each group at the same time point in stable and deep anesthesia,as well as the time to loss of righting reflex and return of righting reflex(LORR/RORR).Results Compared with that before light stimulation,BSR in ChR2 group decreased(P＜0.05)and BSR in GtACR group increased(P＜0.05)during light stimulation,while there was no statistical difference in mCherry group(P＞0.05).In the chemogenetic experiment,compared with mCherry group,the percentage of total power of α,β and γ band of cortical EEG in hM4Di group was significantly increased under deep anesthesia(P＜0.05),while that in hM3Dq group was not significantly different(P＞0.05).There was no significant difference in the time to LORR between hM3Dq group and hM4Di group(P＞0.05),but the time to RORR was shortened in hM3Dq group and prolonged in hM4Di group(P＜0.01).Conclusion Glutamatergic neurons in BLA are involved in regulating arousal from isoflurane anesthesia in mice.Activation of BLA glutamatergic neurons can significantly promote arousal from isoflurane anesthesia in mice.
维普
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