nNOS遺伝子消去は,心筋梗塞後の病理的な左心室改造と機能的悪化を悪化させる
Dana Dawson1, Craig A Lygate, Mei-Hua Zhang
1Department of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK.
Circulation
|December 14, 2005
まとめ
ニューロン酸化窒素合成酵素 (nNOS) 欠乏症は,左心室の不良改造を加速し,心筋梗塞 (MI) の後のベータ-アドレナジック機能を損なう. 心臓発作におけるnNOSのアップレギュレーションは,保護的適応的メカニズムであるように思われる.
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
- 心筋梗塞の研究
背景:
- 神経性酸化窒素合成酵素 (nNOS) は,正常な心臓および心臓発作の心臓の収縮性を調節することに関与しています.
- 心不全におけるnNOSの活性の増加は,左心室 (LV) の改造と心筋梗塞 (MI) 以後の機能的衰退における役割を示唆しています.
研究 の 目的:
- 心臓発作後の心臓の改造と機能におけるnNOSの役割を調査する.
- nNOS欠乏症が,LV機能不全とMI後の有害な再構成を悪化させるかどうかを判断する.
主な方法:
- MIの1,4,8週後のnNOS-ノックアウト (nNOS(-/-)) とワイルドタイプ (WT) のマウスにおけるLVリモジレーションと血液動力学の比較.
- 3Dエコーカルディオグラフィとプレロードリクルート可能な脳卒中作業を使用して,基礎およびドブタミン刺激によるLV収縮性とリラックス性の評価.
主要な成果:
- nNOS(-/-) マウスは,基礎およびベータアドレナジックLVリラクゼーションの障害を示した.
- nNOSが欠けていたマウスは,WTの littermatesと比較して,MI後の加速され,より深刻なLVの拡張を示しました.
- 感染したnNOS (((-/-) の心臓は,WTの心臓とは異なり,ドブタミンに対する反応として収縮性の有意な低下を示した.
結論:
- nNOSは,不良のLVリモデリングを予防し,MI後のベータアドレネルジック・リザーブを保持するために重要です.
- 心臓発作の心臓発作における筋臓のnNOSのアップレギュレーションは,損傷に対する重要な適応反応を表しています.
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