近隣の新皮質のピラミダニューロン間の特殊な阻害シナプス作用
Ming Ren1, Yumiko Yoshimura, Naoki Takada
1Department of Neuroscience, Research Institute of Environmental Medicine, Nagoya University, Nagoya 464-8601, Japan.
Science (New York, N.Y.)
|May 5, 2007
まとめ
マウスの視覚皮質の個々の刺激性ニューロンは,近くの細胞の抑制を誘発することができます. これは,インターニューロンの発火とは独立して,阻害性インターニューロン端末の刺激によって起こります.
科学分野:
- 神経科学は神経科学である.
- 皮質回路は,皮質回路である.
- シナプス伝送はシナプスによる.
背景:
- ピラミッド型のニューロンは,皮質の主要な興奮細胞です.
- 阻害性インターニューロンは,皮質の活動を調節する.
- 興奮性ニューロンが抑制に影響を与える正確なメカニズムは,完全に理解されていません.
研究 の 目的:
- マウスの視覚皮質の単一の刺激性ニューロンが,局所的抑制回路にどのように影響するかを調査する.
- 興奮誘発阻害を媒介するシナプスメカニズムを解明する.
主な方法:
- マウスの視覚皮質におけるin vivo電気生理学.
- ピラミッドニューロンにおけるポストシナプス電流の記録.
- 単層-2/3ピラミッド型ニューロンの刺激.
主要な成果:
- 単一のピラミッド神経細胞の活動は,隣接するピラミッド細胞の抑制性ポストシナプス電流を確実に誘発した.
- この効果は,抑制性インターニューロン端末のアクソアクソン刺激によって媒介された.
- 阻害は,阻害性内ニューロンの体発火とは独立して誘発された.
結論:
- 個々の刺激性ニューロンは,局所的抑制を直接かつ迅速に制御することができる.
- これは,皮質ネットワークの活動を正確に調節するための新しいメカニズムを提供します.
- 刺激性ニューロンは,以前考えられていたよりも抑制の形成により直接的な役割を果たします.
関連する概念動画
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