Jia-Yi Wu, Wei Wang, Xin-Yi Dai, Si He, Fan-He Song, Shao-Jie Gao, Long-Qing Zhang, Dan-Yang Li, Lin Liu, Dai-Qiang Liu, Ya-Qun Zhou, Pei Zhang, Bo Tian, Wei Mei
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引用次数: 0
Abstract
Background: The supramammillary nucleus (SuM), located in the caudal hypothalamus, includes wake-promoting glutamatergic neurones. Their potential role in regulating states of consciousness during general anaesthesia remains unknown.
Methods: We used in vivo fibre photometry, c-Fos staining, chemogenetic and optogenetic manipulations, and electroencephalography/electromyography to explore the roles of glutamatergic SuM neurones (SuMVglut2 neurones) at different phases of sevoflurane anaesthesia. Rabies-mediated retrograde and anterograde tract tracing were used to investigate the monosynaptic glutamatergic inputs from the medial septum (MS) to SuM. Their roles in sevoflurane anaesthesia were investigated by in vivo fibre photometry and optogenetic manipulations.
Results: The population activity of SuMVglut2 neurones decreased at loss of consciousness but increased during recovery of consciousness under sevoflurane anaesthesia. Their activity also decreased during suppression but increased during bursts in sevoflurane-induced burst-suppression oscillations. Activating SuMVglut2 neurones chemogenetically or optogenetically decreased sensitivity to sevoflurane, induced behavioural arousal and cortical activation during continuous steady-state anaesthesia, and stable burst-suppression oscillations under sevoflurane. In contrast, chemogenetic or optogenetic inhibition of SuMVglut2 neurones increased sensitivity to sevoflurane or intensified cortical inhibition during sevoflurane anaesthesia. Retrograde and anterograde tracing verified monosynaptic projections from MSVglut2 neurones to SuMVglut2 neurones. The activity of MSVglut2 SuM terminals increased during loss of consciousness but recovered during recovery of consciousness. Optogenetic activation or inhibition of MSVglut2 SuM terminals induced cortical activation or inhibition, respectively, during sevoflurane anaesthesia.
Conclusions: Activation of SuMVglut2 neurones or the glutamatergic septo-supramammillary circuit induces behavioural arousal and cortical activation during sevoflurane anaesthesia.
期刊介绍:
The British Journal of Anaesthesia (BJA) is a prestigious publication that covers a wide range of topics in anaesthesia, critical care medicine, pain medicine, and perioperative medicine. It aims to disseminate high-impact original research, spanning fundamental, translational, and clinical sciences, as well as clinical practice, technology, education, and training. Additionally, the journal features review articles, notable case reports, correspondence, and special articles that appeal to a broader audience.
The BJA is proudly associated with The Royal College of Anaesthetists, The College of Anaesthesiologists of Ireland, and The Hong Kong College of Anaesthesiologists. This partnership provides members of these esteemed institutions with access to not only the BJA but also its sister publication, BJA Education. It is essential to note that both journals maintain their editorial independence.
Overall, the BJA offers a diverse and comprehensive platform for anaesthetists, critical care physicians, pain specialists, and perioperative medicine practitioners to contribute and stay updated with the latest advancements in their respective fields.