脊椎動物の内在的な昼間振動器によって調節されるカチオンチャンネル
1Program in Neuroscience, Department of Biological Science, Florida State University, Tallahassee 3206-4075, USA.
Nature
|July 11, 1996
まとめ
研究者らは,鶏の桃の細胞で,カルシウムに浸透する新しいチャネル,ILOTを発見しました. このチャンネル,このチャンネル.
科学分野:
- クロノバイオロジー クロノバイオロジー
- 分子生理学 分子生理学
- イオンチャンネル生理学 イオンチャンネル生理学
背景:
- 鶏の桃腺細胞は,メラトニン放出における昼夜リズムを示しています.
- メラトニンの分泌は,循環型AMPと細胞内カルシウム (Ca2+) によって調節されます.
- 増加したCa2+流入は夜間に起こりますが,L型Ca2+チャネル経由では発生しません.
研究 の 目的:
- 鶏の松果細胞における夜間メラトニン分泌中のCa2+の増加に起因する分子メカニズムを特定すること.
主な方法:
- 培養鶏の桃の細胞のパッチクランプ電気生理学.
- 新しい40-pSカチオンチャンネル (ILOT) の特徴.
- ILOTのゲーティング特性と昼夜リズム性の評価.
主要な成果:
- Ca2+に浸透する新しい40-pSカチオンチャンネル,ILOTが特定されました.
- ILOTは,夜に活動しているが,昼間は活動していない,明確なゲート活動を示す.
- ILOTゲーティングにおける日経リズムは,自由走行条件下でも持続し,夜には光無感である.
結論:
- ILOTは,ニワトリの臓細胞におけるCa2+透過性チャネルをリズム的にゲートする新しいチャネルを表しています.
- ILOTの活動は,メラトニン分泌の昼夜調節に寄与する可能性がある.
- ILOTのゲーティングメカニズムは,電圧,ストレッチ,Ca2+,および周期性核酸から独立しています.
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