シナプス伝達は,勝者入力を選択するために不要ですが,シナプス排除の後のイベントには不可欠です
Tzu-Huei Kao1,2, Yuto Okuno1,3, Kyoko Matsuyama1
1Department of Neurophysiology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan.
まとめ
神経伝達物質の放出は,小脳からの入力を選択するのに不可欠ではありません. しかし,シナプス伝達は,シナプス除去と発達中のニューロン接続の精製に不可欠です.
科学分野:
- 神経科学
- 発達生物学
- 細胞生物学
背景:
- ニューロンの配線を洗練することは 適切な脳機能に不可欠です
- 発達中のニューロンインプットの選択におけるシナプス伝達の役割は議論されている.
- 小脳のクライミング・ファイバー (CF) からプルキンジェ細胞 (PC) システムまでの神経回路の精製モデル.
研究 の 目的:
- CFの選択を勝ち取るために神経伝送の必要性を調査する.
- CF-PCシナプス除去と領域拡大におけるシナプス伝達の役割を決定する.
主な方法:
- CFのサブセットから神経伝達物質の放出を消去するために,新生児マウスで光マーカーとテタヌス毒素のライトチェーンを使用した.
- CF-PCシナプスと軸索の競争の発展を観察し分析した.
主要な成果:
- 神経伝達物質の放出に欠陥のあるCFは,依然として"勝者"の入力として選択できます.
- シナプス伝播は,勝利したCFがPCの樹木系に沿ってその領域を拡大するために不可欠でした.
- シナプス伝播は"敗者"のCFを排除する上で重要な役割を果たした.
結論:
- 主要なニューロンの入力の最初の選択にはシナプス伝達は必要ありません.
- 神経伝達はシナプスの除去と回路の精製の次のステップに不可欠です.
- この研究は,神経回路の発達の異なる段階におけるシナプス活動の異なる役割を明確にします.
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