神経伝達物質によって誘発される神経成長の回転
J Q Zheng1, M Felder, J A Connor
1Department of Biological Sciences, Columbia University, New York, New York 10027.
Nature
|March 10, 1994
まとめ
アセチルコリンなどの神経伝達物質は,神経の成長コンを誘導する. この研究では,アセチルコリンは,カルシウムシグナル伝達によって媒介される神経成長コンを惹きつけ,神経発達の神経伝達物質の新しい役割を明らかにしています.
科学分野:
- 神経科学は神経科学である.
- 発達生物学 発達生物学とは
背景:
- 神経成長コンの誘導は,神経の発達に不可欠です.
- 成長は細胞外信号を用いてナビゲートするが,内生化学誘導剤はほとんど知られていない.
- 神経伝達物質は発達初期に存在し,形態発生に影響を与える可能性があります.
研究 の 目的:
- 神経の成長のためのキモアトラクタントとしてのアセチルコリン (ACh) の役割を調査する.
- ACh媒介による成長コンの回転の背後にある分子メカニズムを解明する.
主な方法:
- 定義されたアセチルコリン・グラデーションにさらされた培養神経成長.
- 成長コーンの回転反応を測定する.
- ニコチンのACH受容体とCa2+カルモジュリン依存タンパク質キナーゼIIの薬理学的抑制.
- 細胞内カルシウム ([Ca2+]i) ダイナミクスの光成像.
主要な成果:
- アセチルコリン (ACh) は,神経成長コンの正の回転反応を誘発した.
- この反応には,ニューロンのニコチンのACH受容体と細胞外Ca2+の活性化が必要でした.
- Ca2+-カルモジュリン依存タンパク質キナーゼIIは,シグナル伝達経路に関与していた.
- AChは,成長コンの回転に先立つ細胞溶液中のCa2+濃度 ([Ca2+]i) の急速かつ一時的な増加を誘発した.
結論:
- 神経伝達物質,特にアセチルコレンは,成長コンの誘導のためのキモアトラクタントとして作用することができます.
- サイトソリックCa2+は,成長コンの回転反応を媒介する重要な第2のメッセンジャーとして,ACh.
- これらの発見は,早期の神経発達における神経伝達物質の新たな形質学的役割を強調しています.
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