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Updated: Jun 23, 2025

Isolation of Human Atrial Myocytes for Simultaneous Measurements of Ca2+ Transients and Membrane Currents

Isolation of Human Atrial Myocytes for Simultaneous Measurements of Ca2+ Transients and Membrane Currents

Published on: July 3, 2013

細胞内カルシウムバッファリングの障害は,心房動症の患者の心房筋細胞におけるリズム異常基質に寄与する

Funsho E Fakuade^1,2,3, Dominik Hubricht^2,3, Vanessa Möller^2,3

¹Cluster of Excellence "Multiscale Bioimaging: From Molecular Machines to Networks of Excitable Cells" (F.E.F., A.L., F.S., F.H., S.E.L., A.E., N.V.), Georg-August-University Göttingen, Germany.

|June 24, 2024

まとめ

持続的な心房細動 (persAF) の細胞内カルシウムバッファリングの低下は,心臓のトロポニンC (cTnC) 値の低下と関連しています. この障害は不律症の感受性を高め,persAFの治療目標を示唆する.

科学分野:

心臓病科
分子生物学
バイオ物理学

背景:

細胞内Ca2+バッファリングの変異は,ミオフィラメントタンパク質が関与し,心律不整に関与しています.
持続的な心房細動 (persAF) では心房筋細動の退化が見られるが,Ca2+バッファリングプロファイルは不明である.

研究の目的:

細胞内Ca2+バッファリングを調査する
パースAFにおけるCa2+バッファリングのリズム異常作用を調査する.

主な方法:

パースAF患者と対照群における細胞内Ca2+シグナル伝達と膜経 Ca2+流の同時記録
ヒトの心房のiPSC由来心筋細胞 (iPSC-CMs) を in vitro 研究に使用した.
マウスモデルでの免疫ボルトリングによる量化タンパク質レベルと心臓電気生理学的評価.

主要な成果:

persAF患者からの心房筋細胞は,Ca2+バッファの枯渇により,細胞質のCa2+バッファの減少を示した.
心臓のトロポニンC (cTnC) を含むCa2+結合ミオフィラメントタンパク質の低タンパク質濃度が,パーサAF患者で観察されました.
iPSC- CMにおけるcTnCのノックダウンは,バッファリングの減少と不律性イベントの増加を模倣した;マウスの心臓におけるバッファリングの減少は,心房不律症の脆弱性を増加させた.

結論:

減少したミオフィラメントタンパク質,特にcTnCは,パーソナルAFにおける細胞溶液のCa2+バッファリングを減少させ,自発的なCa2+放出と心房細動を促進する.
細胞内バッファリングメカニズムをターゲットにすることで,persAFの管理のための治療戦略を提供することができます.

キーワード:

心房細動心房の改造カルシウム信号心律乱症電気生理学イオンチャネル

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Isolation of Atrial Myocytes from Adult Mice

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Isolation of High Quality Murine Atrial and Ventricular Myocytes for Simultaneous Measurements of Ca2+ Transients and L-Type Calcium Current

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