グルタミン酸クリアランスとシナプス効果の制御は,ニューロンの膠質覆蓋によって行われます
S H Oliet1, R Piet, D A Poulain
1INSERM U.378, Université Victor Segalen-Bordeaux 2, 33077 Bordeaux, France. stephane.oliet@bordeaux.inserm.fr
Science (New York, N.Y.)
|May 8, 2001
まとめ
アストロサイトはシナプスにおけるグルタミン酸のレベルを調節し,神経細胞のコミュニケーションに影響を与えます. 減少したアストロサイトカバーはグルタミン酸クリアランスを低下させ,シナプス伝達と脳内の神経機能に影響を与えます.
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
- シナプス伝送 シナプス伝送
背景:
- 興奮性シナプス伝達は,中枢神経系の機能に不可欠である.
- グルタミン酸は,主な興奮神経伝達物質である.
- アストロサイトは細胞外環境の調節に重要な役割を果たします.
研究 の 目的:
- ラットの下垂体上視核におけるアストロサイトカバレッジとグルタミン酸クリアランスの関係を調査する.
- グルタミン酸のダイナミクスの変化がシナプス伝達にどのように影響するかを決定する.
- アストロサイトがシナプス効果を調節する役割を明らかにする.
主な方法:
- 興奮性シナプス伝送の電気生理学的分析.
- グルタミン酸クリアランスの薬理学的操作.
- 顕微鏡を用いたアストロサイトカバレッジの評価.
- プレシナプスメタボトロピックグルタミン酸受容体の機能の調査.
主要な成果:
- グルタマートクリアランスと細胞外グルタマート濃度は,アストロサイトクニューロン覆蓋の程度と直接相関しています.
- アストロサイトカバレッジの減少またはグルタミン酸クリアランスの低下は,シナプス前メタボトロピックグルタミン酸受容体の活性を調節する.
- シナプスの有効性は,グルタミン酸ダイナミクスとアストロサイトカバレッジの変化によって変化します.
結論:
- アストロサイトカバレッジは,シナプスのグルタミン酸ホメオスタシスの重要な決定因子です.
- アストロサイトは,グルタミン酸ダイナミクスの調節を通じて,シナプス伝達効率を積極的に調節する.
- アストロサイトは,中枢神経系における適切な神経機能を維持するために不可欠です.
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