ディアストリック心不全における心筋細胞の硬化
Attila Borbély1, Jolanda van der Velden, Zoltán Papp
1Laboratory for Physiology, Institute for Cardiovascular Research, VUMC, Amsterdam, The Netherlands.
Circulation
|February 9, 2005
まとめ
ダイアストリック心不全 (DHF) は,心筋細胞が硬くなり,リラックスが低下する. タンパク質のリン酸化が低下すると,この硬さが起こりうるが,それはタンパク質キナーゼA (PKA) によって逆転することができる.
科学分野:
- 心臓病学 心臓病学
- 分子生物学は分子生物学である.
- バイオフィジックス 生物物理学
背景:
- 保存された左心室放出分数 (EF) によって特徴づけられるダイアストリック心不全 (DHF) は,ますます認識されています.
- DHFの正確な病原遺伝的メカニズムは,限られた心筋組織生検材料のために完全に理解されていません.
- この研究では,心筋筋の特徴を調査するために,DHF患者からの心筋内組織生検サンプルを分析しました.
研究 の 目的:
- DHF患者におけるコラーゲン体積分 (CVF) とサルコメリックタンパク質の組成を分析する.
- DHF患者から分離された心筋細胞の細胞収縮性能を評価する.
- 心筋の特性を,体内ダイアストリック機能不全と相関させるため.
主な方法:
- DHF患者および対照群の内心筋生検サンプルをCVFのために分析した.
- 単一の心筋細胞を隔離し,その収縮性能を評価した.
- 機械的に隔離された心筋細胞は,異なったカルシウム濃度で活性化され,イソメトリック力と静止張力 (F ((受動)) を測定しました.
主要な成果:
- DHFの患者は,対照群と比較して,より高いCVFを示した.
- DHF患者からの心筋細胞は,同様の最大力の発達にもかかわらず,有意に高い静止緊張 (F ((受動)) を示しました.
- F ((受動的) とCVFの組み合わせは,いずれかのパラメータ単独よりも,上昇したLV終端下痢圧 (LVEDP) とよりよく相関していた.
結論:
- DHFは硬直した心筋細胞と関連しており,その証拠は,与えられたサルコメアの長さで受動的緊張が増加していることです.
- 増加したF (パッシブ) とCVFは,DHFにおけるダイアストリック機能不全の重要な決定因子です.
- タンパク質キナーゼA (PKA) がFを減少させる能力 (受動的) は,減少したサルコメリックタンパク質リン酸化がDHFの病原性において役割を果たすことを示唆している.
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