自発的な網膜波の伝播におけるコリナージックシナプス伝播の要件
M B Feller1, D P Wellis, D Stellwagen
1Howard Hughes Medical Institute and Department of Molecular and Cell Biology, University of California, Berkeley, 94720-3200, USA. marla@violet.berkeley.edu
Science (New York, N.Y.)
|May 24, 1996
まとめ
早期発育に不可欠な網膜の自発的な波は,ニコチン受容体をガンジオン細胞に活性化するコリン性アマクリン細胞によって駆動されます. このホルモン系は,視覚が生まれる前に波の伝播に不可欠である.
科学分野:
- 神経科学は神経科学である.
- 発達生物学 発達生物学について
- 網膜生理学 網膜生理学とは
背景:
- 発達中の網膜は,機能的な視力になる数週間前に,アクションポテンシャルの波として自発的な神経活動を示す.
- これらの初期の網膜波は,神経回路の形成において重要な役割を果たすと考えられています.
研究 の 目的:
- 発達中の網膜における自発的な波動活動の基礎となる細胞およびシナプスメカニズムを調査する.
- これらの早期の網膜波を駆動するシナプス入力源を特定するために.
主な方法:
- 光学画像は,網膜波の間の神経活動の空間的なパターンを視覚化するために使用されました.
- シナプス活性化と特定の受容体の役割を評価するために,細胞全体の記録が行われました.
- コリンアセチルトランスフェラーゼに対する抗体による免疫ヒストロケミストリーは,コリン性細胞集団を特定した.
主要な成果:
- 網膜の波は,網膜のギャングリオン細胞層全体にわたる空間的に制限された,モザイク型の活動領域で構成されています.
- 波の生成には,ギャングリオン細胞のニューロンのニコチンアセチルコリン受容体のシナプス活性化が必要です.
- 均等に分布したコレリン性アマクリン細胞は,未成熟の網膜で確認された唯一のコレリン性細胞でした.
結論:
- コリン性アマクリン細胞は,発達中の網膜の網膜のギャングリオン細胞へのシナプス入力の主な供給源です.
- これらのコロリン性アマクリン細胞の活動は,自発的な網膜波の伝播に不可欠です.
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