ペースによって引き起こされる心不全におけるチチンのイソフォーム発現の変化は,受動的な筋肉の硬さの増加を引き起こします
Yiming Wu1, Stephen P Bell, Karoly Trombitas
1Department VCAPP, Washington State University, Pullman 99164-6520, USA.
Circulation
|September 11, 2002
まとめ
心不全はチチンのイソフォームの発現を変化させ,硬いN2Bイソフォームを増加させ,適合するN2BAイソフォームを減少させます. このシフトは,心筋硬直を上昇させ,腹動力機能不全に寄与します.
科学分野:
- 心血管生物学 心血管生物学
- 筋肉生理学 筋肉生理学
- バイオケミストリー バイオケミストリー
背景:
- ティチンタンパク質は,分子スプリングセグメントを通して,受動的な心筋硬化をもたらします.
- 心筋は,異なるスプリング長さのチチンの同型を発現し,硬さに影響を与えます:N2B (硬い) とN2BA (適合).
- 心不全のダイアストリック機能不全は,心筋硬直の変化と関連しています.
研究 の 目的:
- 心不全に起因するダイアストリック機能不全におけるチチンイソフォーム発現の変化を調査する.
- 心不全の進行中にチチンの同型体の発現比が変化するかどうかを判断する.
主な方法:
- タヒカルディア誘発の膨張性心筋症の犬のモデル (4週間のペース) を利用しました.
- 分析されたチチンイソフォーム発現レベルは,コントロールとペースで誘発された心不全の心筋梗塞.
- 測定された受動的な筋肉の硬さとオスカリン表現.
主要な成果:
- コントロールの心筋筋は,N2BとN2BAのチチンの同型体の同様の発現を示した.
- 拡張性心筋症のモデルは,合計チチンの量を変えることなく,N2Bイソフォームの発現の増加へのシフトを示した.
- このシフトは,チチンベースの受動的な筋肉の硬さの上昇と相関していた.
- オブスクーリンの発現は,ペースモデルでは著しく上位調節された.
結論:
- パッシブ心筋硬直の調節は,チチンのイソフォーム表現比率を調整することによって達成されます.
- 犬の心不全モデルでは,このメカニズムが示され,心筋硬直度が増加します.
- 変化したチチンのイソフォーム発現は,心不全で観察されるダイアストリック機能障害に関与しています.
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