単一デンドリット状の棘における長期増強の構造的基礎
Masanori Matsuzaki1, Naoki Honkura, Graham C R Ellis-Davies
1Department of Cell Physiology, National Institute for Physiological Sciences and The Graduate University of Advanced Studies (Sokendai), Myodaiji, Okazaki 444-8787, Japan.
Nature
|June 11, 2004
まとめ
脊髄の構造は活動によって変化し,学習と記憶の基礎となる. 小さな棘は,長期の増強の鍵であり,大きな棘は長期の記憶を蓄積する可能性がある.
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
- シナプスの可塑性
背景:
- ピラミッド状の神経細胞のデンドリティック脊椎は,学習と記憶のための提案された細胞基礎である活動に依存した構造の再構築を経験します.
- 構造再構築がシナプス可塑性を支える正確なメカニズムは,長期増強 (LTP) と,個々の脊椎レベルでの入力特異性は不明のままです.
研究 の 目的:
- 単一 dendritic 脊椎レベルでの長期増強 (LTP) の構造的基盤を調査する.
- シナプス性可塑性が個々の脊椎で入力特異であるかどうかを判断する.
主な方法:
- ハイポキャンパスのCA1ピラミッドニューロンの単一の脊椎で可塑性を誘導するために,ケージンググルタミン酸の2フォトン光解を活用しました.
- 制御されたグルタミン酸解禁に反応した構造的変化と関連するシナプス電流の変化を調べた.
主要な成果:
- 繰り返されたグルタミン酸脱皮は,迅速で選択的な脊椎の拡大を誘発した.
- 膨張は,大きなキノコの棘では一時的であったが,小さな棘では持続した.
- 脊椎の拡大はAMPA受容体電流の増加と相関しており,NMDA受容体,カルモジュリン,アクチンポリメリゼーションに依存していた. 長期にわたる拡張には,Ca2+/カルモジュリン依存タンパク質キナーゼII.
結論:
- 個々の樹枝状のは,ヘッブの学習の仮説に固執する.
- 小さい棘は,長期の増強を誘発するための好ましい場所であるようです.
- 大きな棘は,長期記憶の痕跡の物理的保管庫として機能する.
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