コメント "局所無透性アニオンはニューロンの塩化物濃度を確立する"

Juha Voipio¹, Walter F Boron², Stephen W Jones²

¹Department of Biosciences, University of Helsinki, Helsinki, Finland. juha.voipio@helsinki.fi.

Science (New York, N.Y.)

|September 6, 2014

まとめ

局所無透性アニオンは,ニューロン塩化物濃度を確立することができず,Glykys et al.の発見と矛盾しています. これは,神経機能とGABAAR電流を支配する熱力学原理に挑戦しています.

科学分野:

神経科学は神経科学である.
細胞生物学細胞生物学
バイオフィジックス生物物理学

背景:

ニューロンの塩化物濃度は,GABAAR電流経由の抑制性神経伝達を調節するために重要である.
確立された理解は,電化学的梯度を維持するイオントランスポーターを含む.
Glykys et al. グラキースと仲間たち不浸透アニオンを含む代替メカニズムを提案した.

研究の目的:

Glykys et al. が提案したメカニズムの熱力学的可行性を批判的に評価する.
ニューロンの塩化物濃度における局所無透性アニオンの役割を決定する.
発見を熱力学の基本原理と調和させる.

主な方法:

イオン輸送と濃度グラデーションの熱力学分析.
ニューロン塩化物ホメオスタシスの理論モデリング.
既存の文献と提案されたメカニズムのレビューと批判.

主要な成果:

Glykys et al. が提案したメカニズム熱力学の第二法則に違反する.
透かし不可能なアニオンを通した神経塩化物濃度を確立するには,永続的なイオン運動機械が必要になります.
イオントランスポーターは,神経細胞の塩化物グラデーションを維持するために不可欠です.

結論:

Glykys et al.による結論について熱力学的に不可能である.
ニューロンの塩化物濃度は,被動的なアニオン蓄積ではなく,活性イオン輸送メカニズムによって調節されます.
この発見は,神経科学の研究において熱力学原理に従うことの重要性を強調している.

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