フォトトレーニングと瞳孔光の反射は,異なったipRGCの集団によって媒介されます
S-K Chen1, T C Badea, S Hattar
1Department of Biology, Johns Hopkins University, Baltimore, Maryland 21218, USA.
Nature
|July 19, 2011
まとめ
本質的に光敏感な網膜のギャングリア細胞 (ipRGCs) は,異なるサブタイプを持っています. Brn3b-ネガティブなipRGCsは昼夜リズムを制御し,Brn3b-ポジティブなipRGCsは瞳孔光の反射 (PLR) を調節する.
科学分野:
- 神経科学は神経科学である.
- オフタルモロジック (眼科)
- クロノバイオロジーはクロノバイオロジーを用います.
背景:
- 本質的に光敏感な網膜のギャングリア細胞 (ipRGCs) はメラノプシンを発現し,光に依存する機能に不可欠です.
- ipRGCsは,昼間照射運動と瞳孔光の反射 (PLR) を調節する.
- 以前の研究では,ipRGCsの役割が示されていたが,詳細なサブ集団分析は欠けていた.
研究 の 目的:
- Brn3b転写因子発現に基づくipRGCの異なるサブ集団を調査する.
- これらのipRGCサブ集団と,光媒介反応におけるそれらの特定の役割を機能的に区別する.
主な方法:
- ipRGC亜集団を選択的にターゲットにするために,遺伝子アブレーション技術を使用した.
- 脳内のBrn3b陰性およびBrn3b陽性ipRGCの内置パターンを調べました.
- 選択的アブレーションが昼間照射訓練とPLRに与える影響を評価した.
主要な成果:
- 2つの異なるipRGCサブ集団を特定しました: Brn3b陰性M1ipRGCとBrn3b陽性ipRGCです.
- Brn3b陰性M1ipRGCsは,昼間リズムに不可欠な上下神経核 (SCN) を刺激する.
- Brn3b陽性ipRGCsは,オリヴァリ前葉核および他の脳領域を神経化させ,PLRを媒介する.
- Brn3b陽性ipRGCsの選択的アブレーションにより,PLRは廃止されたが,昼間光訓練は維持された.
結論:
- ipRGCは,Brn3b表現で定義された機能的に異なるサブ集団で構成されています.
- Brn3b陰性M1ipRGCsは,昼夜照射訓練に不可欠である.
- Brn3b陽性ipRGCは,瞳孔光の反射 (PLR) の調節に不可欠である.
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