持続的防御状態の刺激特有の下垂体エンコーディング
Ann Kennedy1, Prabhat S Kunwar1,2, Ling-Yun Li1
1Division of Biology and Biological Engineering, Tianqiao and Chrissy Chen Institute for Neuroscience, California Institute of Technology, Pasadena, CA, USA.
Nature
|September 17, 2020
まとめ
中腹下垂体 (VMHdm) のSF1ニューロンの持続的な神経活動は,マウスの持続的な恐怖状態の根底にある. この研究は 刺激特有の下垂体ダイナミクスを示し 作業記憶とは異なる 長期的な感情反応を誘発しています
科学分野:
- 神経科学
- 感情 の 神経 生物学
- 下垂体機能
背景:
- 持続的な神経活動は,皮質と海馬のネットワークで作業記憶を媒介することが知られている.
- 恐怖のような 内部的な感情状態は 刺激にさらされた後も持続しますが 根底にある神経の動態は よく理解されていません
- ベントロメディアル下垂体 (VMHdm) のNR5A1 (SF1) を発現するニューロンは,防御行動に不可欠である.
研究 の 目的:
- 遅い神経の動態が 持続的な感情状態に 関与しているかどうかを調べる
- 持続的な防御行動と感情状態を媒介するVMHdm SF1ニューロンの役割を調べる.
- 視床下部の神経活動のメカニズムと刺激特異性を解明する.
主な方法:
- マウスにおけるVMHdm SF1ニューロンの光遺伝的活性化と刺激
- 微視内視鏡でカルシウム画像を撮り,神経の活動を記録する.
- 局所的なニューロンの接続性を研究するために急性脳断片のカルシウムイメージング.
- 防御反応を評価するための行動分析 (オープンフィールド)
- ニューラルダイナミクスを分析する計算モデルです.
主要な成果:
- VMHdm SF1ニューロンは 自然的な脅威に反応して 数十秒間の持続的な活動を示します
- この持続的な活動は 持続的な防御行動と相関し 必要なものです
- 異なるVMHdm SF1サブポピュレーションは,異なる脅威様式によって活性化され,刺激特異性を示す.
- VMHdm SF1ニューロン間には局所刺激的接続性がある.
- 持続的な活動は,集団レベルでの個々のニューロン間の異質なダイナミクスを反映します.
結論:
- VMHdm SF1ニューロンは 刺激特有で遅い神経動態を示し 恐怖のような持続的な感情状態に寄与します
- 作業記憶に含まれるものよりも ずっと長い時間軸で動きます
- この発見は 持続的な感情的な経験の ニューラル基盤の 新しいメカニズムを明らかにしています
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