コクレア増幅は,コクレア核のシナプスの終端にあるシナプス伝送を調節する

Fang Wang¹, Yige Li¹, Geng-Lin Li^2,3

¹Department of Otorhinolaryngology, ENT institute, and NHC Key Laboratory of Hearing Medicine, Eye & ENT Hospital, Fudan University, Shanghai, 200031, China.

The Journal of neuroscience : the official journal of the Society for Neuroscience

|February 17, 2026

まとめ

外部毛細胞による頭増幅は,聴覚神経信号に重大な影響を及ぼします. この増幅をマウスで除去すると,脳幹のシナプス機能が変化し,細胞の興奮性を高め,信号の強度を低下させました.

科学分野:

神経科学は神経科学である.
聴覚系生理学聴覚系生理学
センサリートランスデュークションセンサリートランスデュークション

背景:

哺乳類の内にある外部の毛細胞 (OHCs) は,音の振動を増幅し,聴覚のダイナミックレンジを拡大します.
この頭増幅が中央聴覚処理とニューラルコーディングに与える影響は十分に理解されていません.
この相互作用を理解することは,聴覚信号処理を理解するために不可欠です.

研究の目的:

コクレア増幅の欠如が,中央聴覚経路におけるシナプス伝送にどのように影響するかを調査する.
コクリアの増幅が遺伝的に除去されたときに,コクリア核の機能的変化を検査する.
周辺聴覚処理と中枢神経回路の相互作用を明らかにする.

主な方法:

使用されたプレスティン・ノックアウト (Prestin-/-) マウスは,コクリアの構造を保ちながらコクリアの増幅を排除しました.
聴覚神経繊維と内核の茂った細胞の間のホールド・シナプスのエンド・バルブで,電気生理学的に評価されたシナプス伝達.
茂った細胞の興奮性,シナプス強度,ペアパルス可塑性における変化を分析した.

主要な成果:

Prestin-/-マウスでは,静止膜ポテンシャルと入力レジスタンスが変化したため,ブッシー細胞の興奮性が有意に増加しました.
Heldのエンドバルブにおけるシナプス強度は大きく低下し,RRP (Rightly Releasable Pool) の小胞の減少に関連していた.
ペアリングパルス可塑性は,うつ状態 (WT) から緩和状態 (Prestin-/-) に逆転し,より迅速なRRP補充を示唆しました.

結論:

コクレア増幅の欠如は,コクレア核内のシナプス伝送を大幅に変化させます.
これらの発見は,周辺音処理と中央聴覚回路の間の活発な相互作用を強調しています.
この相互作用は,哺乳類で見られる聴覚のダイナミック範囲の拡大に寄与する.

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