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カルシウムのない去極化は,網膜ニューロンからガンマ-アミノ黄油酸を放出することができます
1Department of Pharmacological and Physiological Sciences, University of Chicago, IL 60637.
Science (New York, N.Y.)
|October 16, 1987
まとめ
網膜の神経細胞からの神経伝達物質の放出は,カルシウムの流入なしに起こる可能性があります. この研究は,電圧の変化だけでガンマ-アミノバター酸の放出を引き起こし,新しいシグナル伝達経路を示唆することを示しています.
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
- 神経生理学 神経生理学とは
背景:
- 神経伝達物質の放出は通常,カルシウムに依存しています.
- 一部の網膜ニューロンは,カルシウムに依存しない放出メカニズムを利用する可能性があります.
- 細胞内カルシウム貯蔵と電圧による放出の役割は不明である.
研究 の 目的:
- カルシウムの流入とは無関係な電圧の変化が,網膜神経細胞における神経伝達物質の放出を調節できるかどうかを調査する.
- 網膜におけるシナプス伝達のための代替メカニズムを探求する.
主な方法:
- 単一魚の網膜ニューロン (水平および双極細胞) の分離および共同培養.
- 細胞間通信を研究するための電気生理学的記録.
- 細胞内カルシウムバッファリングを操作し,カルシウムの侵入を阻害する.
主要な成果:
- 水平細胞の去極化は,ガンマ-アミノバター酸の放出を誘導した.
- カルシウムの流入が遮断され,内部カルシウムがバッファリングされた場合でも,放出が発生しました.
- 観察された放出率と量は,シナプス伝達における役割を支持しました.
結論:
- 網膜ニューロンは,カルシウムに依存しないメカニズムを通じて,ガンマ-アミノバター酸などの神経伝達物質を放出することができます.
- 電圧の変化は,送信機の放出を直接調節し,新しい信号伝送経路を提供することができます.
- この発見は,網膜における神経伝達のためのカルシウム流入の普遍的な要件に異議を唱える.
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