2023-09-21 インペリアル・カレッジ・ロンドン(ICL)
◆この研究から、人間も睡眠の準備について無意識の衝動に支配されている可能性があり、睡眠の適切な準備は生存機能として存在し、真剣に考えるべきだと示唆されている。研究者は今後、前頭前野の細胞が疲労時にどのように活性化され、脳が疲労を感知する仕組みを解明し、なぜ私たちは眠るのかという神経科学の大きな問いに答える手掛かりを探る予定だ。
<関連情報>
- https://www.imperial.ac.uk/news/247873/getting-ready-controlled-specific-brain-wiring/
- https://www.nature.com/articles/s41593-023-01430-4
前頭前野のソマトスタチンニューロンが視索前野と視床下部を経由して睡眠準備行動と睡眠を開始する Somatostatin neurons in prefrontal cortex initiate sleep-preparatory behavior and sleep via the preoptic and lateral hypothalamus
Kyoko Tossell,Xiao Yu,Panagiotis Giannos,Berta Anuncibay Soto,Mathieu Nollet,Raquel Yustos,Giulia Miracca,Mikal Vicente,Andawei Miao,Bryan Hsieh,Ying Ma,Alexei L. Vyssotski,Tim Constandinou,Nicholas P. Franks & William Wisden
Nature Neuroscience Published:21 September 2023
DOI:https://doi.org/10.1038/s41593-023-01430-4
Abstract
The prefrontal cortex (PFC) enables mammals to respond to situations, including internal states, with appropriate actions. One such internal state could be ‘tiredness’. Here, using activity tagging in the mouse PFC, we identified particularly excitable, fast-spiking, somatostatin-expressing, γ-aminobutyric acid (GABA) (PFCSst-GABA) cells that responded to sleep deprivation. These cells projected to the lateral preoptic (LPO) hypothalamus and the lateral hypothalamus (LH). Stimulating PFCSst-GABA terminals in the LPO hypothalamus caused sleep-preparatory behavior (nesting, elevated theta power and elevated temperature), and stimulating PFCSst-GABA terminals in the LH mimicked recovery sleep (non-rapid eye-movement sleep with higher delta power and lower body temperature). PFCSst-GABA terminals had enhanced activity during nesting and sleep, inducing inhibitory postsynaptic currents on diverse cells in the LPO hypothalamus and the LH. The PFC also might feature in deciding sleep location in the absence of excessive fatigue. These findings suggest that the PFC instructs the hypothalamus to ensure that optimal sleep takes place in a suitable place.
