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プレセニリンは,神経伝達物質の放出を調節するために不可欠です
Chen Zhang1, Bei Wu, Vassilios Beglopoulos
1Center for Neurologic Diseases, Brigham & Women's Hospital, Program in Neuroscience, Harvard Medical School, Boston, Massachusetts 02115, USA.
Nature
|July 31, 2009
まとめ
プレセニリン遺伝子の変異が家族性アルツハイマー病を引き起こす. この研究では,プレセニリンは,神経伝達物質の放出とシナプス可塑性に影響を及ぼし,前シナプス機能に決定的な役割を果たし,アルツハイマー病の病原性における初期の前シナプス機能不全を示唆しています.
科学分野:
- 神経科学は神経科学である.
- 遺伝学 遺伝学とは
- 分子生物学は分子生物学である.
背景:
- プレセニリン遺伝子の変異は,家族性アルツハイマー病 (AD) の主要な原因です.
- プレセニリン機能障害はADの病原性におけるシナプス機能障害と関連しています.
- ADにおけるシナプス機能障害の特定の役割と位置は不明である.
研究 の 目的:
- シナプス機能におけるプレセニリンの正確な役割を調査する.
- プレセニリンの機能障害がプレシナプス神経またはポストシナプス神経に影響するかどうかを判断する.
- プレセニリンがシナプス可塑性および神経伝達物質の放出に影響を与えるメカニズムを解明する.
主な方法:
- マウスモデルにおける特定のニューロン集団 (前シナプスCA3対後シナプスCA1) でのプレシリンの条件付き遺伝的不活性化.
- 長期増強 (LTP) と短期可塑性を評価するための電気生理学的記録.
- MK-801を使用してグルタミン酸の放出確率の測定.
- エンドプラズマ網膜のCa2+) 貯蔵物の薬理学的操作.
主要な成果:
- プレシナプス,しかしポストシナプスではない,プレシニリンの削除は,theta-burst誘発のLTPを減少させた.
- プレセニリンのプレシナプス不活性化により,短期的な可塑性およびシナプス促進が変化しました.
- プレシナプスプレセニリンの不活性化により,誘発されたグルタミン酸の放出の可能性が低下した.
- エンドプラズマ網膜のCa(2+) 信号伝達の障害は,シナプス前プレシニリン不活性化の効果を模倣し,遮断しました.
結論:
- プレセニリンは,神経伝達物質の放出とLTP誘導の活動依存的調節において選択的な役割を果たします.
- プレセニリンは,プレシナプス端末の細胞内Ca2+) 放出を調節する.
- プレセニリン喪失によって介されるプレシナプス機能不全は,アルツハイマー病の神経変性症候群の初期のイベントである可能性があります.
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