成人霊長類の新皮質における神経生成なしの細胞増殖
1Department of Neurobiology, Yale University School of Medicine, New Haven, CT 06510, USA.
Science (New York, N.Y.)
|December 12, 2001
まとめ
新しいニューロン形成 (ニューロゲネシス) は,成人のマカクの脳で研究されました. 研究者らは新皮質に新しいニューロンの証拠が見つかりませんでしたが,以前の主張に異議を唱えました.
科学分野:
- 神経科学は神経科学である.
- 霊長類の脳の研究
- 細胞生物学 細胞生物学
背景:
- 最近の主張は,成人のマカクの新皮質に新しいニューロンが継続的に追加されていることを示唆しています.
- この主張は,より高い認知機能と脳の可塑性を理解するための重要な意味を持つ.
研究 の 目的:
- マカク類の猿の新皮質に成人のニューロゲネシスの存在を調査する.
- 霊長類の新皮質で進行中のニューロン添加の主張を検証または反論する.
主な方法:
- 免疫光三重ラベリング技術を使用しました.
- DNA複製の指標としてブロモデオキシユリジン (BrdU) を採用した.
- 細胞タイプを特定するために,神経細胞と膠質細胞の特定のマーカーを使用しました.
主要な成果:
- ニューコルテックスを含む脳壁全体で,多数の BrdU ラベルの細胞が観察されました.
- これらの標識された細胞は,新しいニューロンではなく,非ニューロン細胞として識別されました.
- 新しいニューロン生成の証拠は,海馬と嗅覚球に限られていた.
結論:
- この研究では,正常な成人の霊長類の新皮質におけるニューロゲネシスを支持する証拠は見つかりませんでした.
- 結果は,マカクにおける新皮質神経生成に関する以前に報告された発見が不正確である可能性があることを示しています.
- 成人マカクのニューロン生成は,海馬と嗅覚球のような特定の脳領域に限定されているようです.
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