棒と円のシナプス伝送の運動の違い

J L Schnapf, D R Copenhagen

Nature

|April 29, 1982

まとめ

脊椎動物の網膜の光受容体 (棒と) は,異なる速度で光に反応する. 棒と円の信号を水平細胞にシナプス的に転送することは,これらの異なる応答速度を反映します.

科学分野:

神経科学は神経科学である.
ビジョンビジョン科学科学
網膜生理学網膜生理学とは

背景:

脊椎動物の網膜の光受容体である棒とは,光にさらされるとハイパーポラライズする.
フォトレセプター反応の動態は大きく異なっており,ロッドはコーンよりも約10倍遅い.

研究の目的:

棒とから共有されたポストシナプス水平細胞へのシナプス信号伝達の増幅と時間的特性を調査する.
シナプス信号の伝送速度が,最初の光受容体応答の速度と相関するかどうかを判断する.

主な方法:

網膜の神経細胞からの電気生理学的記録.
光受容体と水平細胞間のシナプス移転運動学的分析.
棒媒介経路とコーン媒介経路からの信号速度の比較.

主要な成果:

棒との両方から水平細胞へのシナプス信号の転送が観察されました.
棒から水平の細胞シナプスでの信号伝達の動態は,円から水平の細胞シナプスでのものより著しく遅かった.
シナプス信号伝達の時間的性質は,棒と円の既知の応答速度と密接に一致していました.

結論:

初期の視覚経路におけるシナプス信号伝達の速度は,シナプス前光受容体の運動学によって決定されます.
この発見は,光受容体の反応速度が視覚処理の時間動態を形作る上で重要であることを強調しています.
パラレル運動は,異なるタイプの光受容体から下流の神経細胞への視覚情報の忠実な伝達を保証します.

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