nNOS基因缺失加剧了心肌梗塞后的病态左心室重塑和功能恶化
Dana Dawson1, Craig A Lygate, Mei-Hua Zhang
1Department of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK.
Circulation
|December 14, 2005
概括
神经氧化合成酶 (nNOS) 缺陷加速左心室不良重塑,并在心肌梗塞 (MI) 后损害β-上腺功能. 在心脏病发作中,nNOS的升级似乎是一种保护性适应机制.
科学领域:
- 心血管生理学心血管生理学
- 分子心脏病学分子心脏病学
- 心肌梗塞研究研究
背景情况:
- 神经性氧化合成酶 (nNOS) 参与调节正常心脏和心脏病发作的心脏收缩性.
- 心脏衰竭中的nNOS活性增加表明在左心室 (LV) 重塑和心肌梗塞 (MI) 后的功能衰退中发挥了作用.
研究的目的:
- 调查nNOS在心脏重塑和心脏功能中扮演的角色.
- 为了确定nNOS缺乏是否会加剧LV功能障碍和心脏病发作后的不良重塑.
主要方法:
- 在心脏病发作后1,4周和8周的nNOS-knockout (nNOS(-/-)) 和野生型 (WT) 小鼠中,LV重塑和血液动力学的比较.
- 使用3D心声学和预加载可招募的中风工作评估基底和dobutamine刺激的LV收缩性和放松性.
主要成果:
- nNOS(-/-) 小鼠表现出基底和β-上腺体LV放松功能受损.
- 与WT littermates相比,缺乏nNOS的小鼠在MI后表现出加速和更严重的LV扩张.
- 患有心脏病的nNOS(-/-) 心脏在对dobutamine的反应中表现出显著的收缩性下降,与WT心脏不同.
结论:
- 在心脏病发作后,nNOS对于预防不良的LV重塑和保持β-上腺素储备至关重要.
- 在心脏病发作中,肌肉动脉nNOS的上调代表了对损伤的显著适应性反应.
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