タラモ皮質のシナプスのカイナート受容体の発達および活動依存の調節

F L Kidd¹, J T Isaac

¹MRC Centre for Synaptic Plasticity, Department of Anatomy, University of Bristol, UK.

Nature

|August 17, 1999

まとめ

発達する脳シナプスは,AMPA受容体と共にカイナート受容体を使用する. その機能は経験依存の可塑性とともに低下し,発達中のカイナート受容体の活動依存の調節を示唆する.

科学分野:

神経科学は神経科学である.
シナプス伝送シナプス伝送
受容器の機能受容器の機能について

背景:

哺乳類の脳における急速な刺激性シナプス伝播は,AMPA,NMDA,カイナート亜型を含むイオノトロプ的グルタミン酸受容体に依存する.
カイナート受容体は中枢神経系で広く発現しているが,その正確な機能はほとんど特徴づけられていない.
最近の薬理学的ツールの進歩により,AMPAとカイナート受容体の区別がより良くなり,機能研究が容易になりました.

研究の目的:

タラモ皮質シナプスの発達におけるカイネート受容体の役割と調節を調査する.
カイネート受容体がAMPA受容体と共にポストシナプス的に存在するかどうかを判断する.
カイネート受容体の機能の発達調節と可塑性を調査する.

主な方法:

タラモ皮質シナプスの発達時の電気生理学的記録.
AMPAとカイナート受容体の貢献を区別するための薬理学的操作.
経験依存の可塑性およびin vitroの長期増強の臨界期間の調査.

主要な成果:

発育中のタラモ皮質シナプスは,ポストシナプスカイナート受容体とAMPA受容体の両方を発現しますが,それらはコロカライズされません.
カイネート受容体のシナプス伝送への貢献は,可塑性の重要な期間中に減少します.
カイナート受容体の機能の同様の低下は,長期の増強をインビトロで誘導した後に観察されています.

結論:

カイナート受容体は,タラモ皮質のシナプスの発達に存在し,伝播への貢献は動的に調節されます.
活動に依存するメカニズムは,重要な発達期間のカイネート受容体の発現または機能を調節する.
これは,シナプス性可塑性と脳の発達におけるカイナート受容体の役割を示唆しています.

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