ジュクスタグロメルーラ細胞群内のカルシウム振動は,レニンの放出を制御する
Hiroki Yamaguchi1, Nick A Guagliardo2, Laura A Bell2
1Department of Pediatrics, Child Health Research Center, University of Virginia School of Medicine, Charlottesville. (H.Y., M.Y., D.M., F.X., J.P.S., S.C., L.F.A., S.M., R.A.G., M.L.S.S.-L.).
Circulation research
|September 3, 2025
まとめ
血圧を調節するために調整されたカルシウム信号を使用します. これらの信号は,カルシウムの放出と吸収を伴うもので,最終的にレニンの分泌を抑制します.
科学分野:
- 腎臓科
- 心血管の生理学
- セルラー・シグナル
背景:
- 血圧と液体のバランスを調節する
- 低血圧に反応してレニン- 血管新生系を活性化します
- アンジオテンシンII (Ang II) は通常,細胞内カルシウム (Ca2+) によるレニン放出を阻害する.
研究 の 目的:
- ジュクスタグロメルーラ細胞における細胞内Ca2+シグナル伝達のダイナミクスと源を調べる.
- このCa2+シグナルが ジュクスタグロメルーラ細胞群の中でどのように組織されているかを理解する.
- レニン分泌の調節とCa2+シグナリングパターンを関連付ける.
主な方法:
- ジュクスタグロメル細胞特異的なCa2+指標 (GCaMP6f) を生成したマウス.
- 浸透した腎臓のスライスでex vivo Ca2+イメージングを行い,本来の腎臓でin vivoイメージングを行った.
- Ang II,Ca2+チャネル阻害剤,ロサルタンを使用し,レニン分泌をELISAで測定した.
主要な成果:
- Ang II刺激により,ジュクスタグロメルーラ細胞群における細胞内Ca2+振動が調整され,拡散した.
- これらの振動は,エンドプラズマ網膜のCa2+放出,ORAIチャネル,およびギャップ・ジャンクションを含んでいる.
- in vivo と ex vivo のイメージングは,レニン分泌と逆相関する類似した Ca2+ 振動パターンを示した.
結論:
- アンジオテンシンIIは,ジュクスタグロメルーラ細胞における細胞内および細胞間Ca2+振動を調整する.
- これらの信号は,ER Ca2+の放出,ORAIチャネル,およびギャップジャンクションによって媒介されます.
- このCa2+の振動はレニンの分泌を抑制し,血圧の恒常化に寄与する.
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