アデニリルサイクラース6型の欠失は,カルシウム処理の障害を通じた左心室の機能を低下させる
Tong Tang1, Mei Hua Gao, N Chin Lai
1Department of Medicine, University of California, San Diego, USA.
Circulation
|December 12, 2007
まとめ
マウスにおけるアデニリルサイクラゼ6 (AC6) 欠失は,cAMPの産生とカルシウム処理を減少させることにより,心臓機能を損なう. これはAC6を強調しています.
科学分野:
- 心血管生理学 心血管の生理学
- 分子心臓病学 分子心臓病学
- Gタンパク質結合受容体シグナル伝達
背景:
- アデニリルサイクラゼ (ACs) は,Gタンパク質結合受容体効果因子である.
- アデニリルサイクラゼ5 (AC5) とアデニリルサイクラゼ6 (AC6) は,心筋細胞で高度に発現しています.
- 心臓におけるAC6の特定の生理学的役割は未定義のままである.
研究 の 目的:
- 心臓の生理学におけるアデニリルサイクラゼ6 (AC6) の特定の役割を調査する.
- 大人の心臓におけるAC6欠失の機能的影響を決定する.
- 心臓機能におけるAC5とAC6の違いを明らかにする.
主な方法:
- Adenylyl cyclase 6 (AC6) の標的型デレーションを施したトランスジェニックマウスを生成した.
- 左心室の収縮機能とリラクゼーションを評価した.
- ベータアドレナゲン受容体刺激によるcAMP生成と,心筋細胞におけるタンパク質キナーゼA活性を測定した.
- 評価されたフォスフォランバンのリン酸化,サルコプラズマ網膜のCa2+-ATPase活性,および一時的なカルシウム形成.
主要な成果:
- AC6の欠失により,左心房の収縮機能とリラックスが著しく低下した.
- AC6の欠如は,cAMPの産生とタンパク質キナーゼAの活性に顕著な減少をもたらした.
- AC6の欠失は,フォスフォランバン・リン酸化とサルコプラズマ網膜のCa2+-ATPase活性低下を含む,カルシウム処理の障害をもたらした.
結論:
- AC6の消去による心臓のcAMP生成とカルシウム処理の障害は,左心室機能の異常の原因である.
- アデニリルサイクラゼ6は,成人の心臓生理学において,重要な非冗長な役割を果たします.
- AC6は,AC5と異なる心臓のユニークな生物学的機能を果たしています.
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