シュヴァン細胞は,発達中のアクションポテンシャルに対する反応をシュヴァン細胞に与えます
1Laboratory of Developmental Neurobiology, National Institutes of Health, National Institute of Child Health and Human Development, Building 49, Room 5A38, 49 Convent Drive, Bethesda, MD 20892, USA.
Science (New York, N.Y.)
|March 24, 2000
まとめ
発達中の軸索における神経衝動活動は,シュヴァン細胞 (SC) の増殖と分化を阻害する. このアデノシントリフォスファート (ATP) の媒介によるニューロン・グリア信号伝達は,適切な信号が受信されるまで,SCの成熟とミエリン化を遅らせます.
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
- 細胞シグナル伝達 細胞信号伝達
背景:
- シュヴァン細胞 (SCs) は神経発達の遅い段階で軸索を分化してミエリン化します.
- SCの成熟は,機能的感覚軸索にとって非常に重要です.
研究 の 目的:
- SCの増殖と分化を調節する軸索インパルス活動の役割を調査する.
- 発達中のニューロン-SC通信の基礎となる分子メカニズムを解明する.
主な方法:
- 神経系モデルの開発でニューロン-SCの相互作用を研究した.
- アデノシントライホスファート (ATP),P2受容体,細胞内カスケード (Ca2+,Ca2+/カルモジュリンキナーゼ,MAPK,CREB) を含むシグナル伝達経路の調査.
- SC分化マーカー (O4,ミエリンベースのタンパク質) と転写因子 (c-fos,Krox-24) の評価表現.
主要な成果:
- プレミエリン化されたアクソンにおけるインパルス活動は,SCの増殖と分化を阻害する.
- SCsのP2受容体を通して作用するATPは,この抑制性ニューロン-膠質シグナル伝達を媒介する.
- ATPシグナリングは,未成熟状態のSCを逮捕し,ミエリン化と主要な分化マーカーの発現を防ぐ.
結論:
- アクソンの活動は,SCの成熟を活発に調節し,分化を遅らせます.
- このメカニズムは,適切な軸索由来信号が端末の分化とミエリン化を引き起こすまで,SCが未分化であることを保証します.
- ATP経由のニューロン-膠質シグナル伝達は,神経系の発達を調整するために重要である.
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