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人类的非常低频RR间隔振荡背后的机制
J A Taylor1, D L Carr, C W Myers
1Department of Internal Medicine, Hunter Holmes McGuire Department of Veterans Affairs Medical Center, and Medical College of Virginia, Virginia Commonwealth University, Richmond, USA. ataylor@mail.hrca.harvard.edu
Circulation
|August 26, 1998
概括
非常低频率的心率变化,对于心脏病发作后的生存至关重要,主要是由副交感神经系统驱动的. 氨酸- ангиотензин- алдостерон系统也起着作用,但阴道音调是心血管健康的关键.
科学领域:
- 心血管生理学心血管生理学
- 自主神经系统的调节规则
- 心率变化分析心率变化分析
背景情况:
- 降低非常低频 (VLF) RR间隔变异性与心肌梗塞后患者的存活率较差有关.
- 对于VLF振荡的生理基础仍然不完全理解.
- 这项研究研究了同情性,阴道和-血管-阿尔多斯特系统在VLF变异性中的作用.
研究的目的:
- 阐明自主和激素对VLFRR间隔变化的贡献.
- 为了区分β-上腺体,副交感和ACE阻塞对VLF振荡的影响.
- 了解健康年轻人体内VLF变异性的生理基础.
主要方法:
- 在躺卧和倾斜姿势的10名健康受试者中记录了RR间隔和动脉压.
- 药物阻断包括盐水 (控制),阿提诺洛尔 (β阻断),阿特罗平 (对交感阻断),联合阻断和埃纳拉普利拉特 (ACE阻断).
- 快速里埃变换分析量化了在非常低,低和呼吸频段的光谱功率.
主要成果:
- 在VLF频段中,用氨酸进行的偏交阻塞极大地降低了总体RR间隔变化率92%.
- β-上腺阻塞没有显著影响VLF或低频功率,但增加了呼吸频率功率.
- ACE阻塞在仰卧姿势中适度增加了VLF功率 (~21%),但在倾斜时没有.
结论:
- VLF RR-间隔节律主要取决于副交感神经系统活动.
- 氨酸- ангиотензин- алдостерон系统对VLF变异性产生次要影响.
- 极低频率振荡的预后意义可能源于它们与副交感功能和心血管健康的强烈关联.
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