在人类心力衰竭中具有悖论性的肌肉交感反射激活
Philip J Millar1, Hisayoshi Murai1, John S Floras2
1From the University Health Network and Mount Sinai Hospital Division of Cardiology, Department of Medicine, University of Toronto, Toronto, Ontario, Canada.
Circulation
|December 4, 2014
概括
在心力衰竭中,减少射出分数 (HFrEF),增加填充压力矛盾地通过不同的单单元反应激发肌肉交感神经活动,与健康个体不同.
科学领域:
- 心血管生理学心血管生理学
- 神经科学是一个神经科学.
背景情况:
- 肌肉交感神经活动 (MSNA) 在心力衰竭中升高,心力衰竭减少射出分数 (HFrEF).
- 这通常归因于心肺机械受体的抑制反减少.
- 然而,机械受体反涉及不同的单个单元群体,具有相反的反应.
研究的目的:
- 测试单个单元的燃烧比例是否矛盾地随着HFrEF的填充压力而增加.
- 调查不同单个单位群体在HFrEF心肺-MSNA反射中的作用.
主要方法:
- 在HFrEF患者和对照中记录下体下负压 (LBNP) 和正压 (LBPP) 的MSNA和中央静脉压力.
- 分类单个单位的MSNA排放为"预期" (经典的负反) 或"悖论" (相反的反应).
主要成果:
- 与对照组相比,LBPP (增加填充压力) 在HFrEF单个单位中引起了矛盾的反射激发,比例较大 (7:18对24:6,P=0.0001).
- 在HFrEF中,LBPP增加了单单单元的平均发射频率,但没有抑制多单元的MSNA.
- 显著比例的HFrEF单元 (12/18) 在增加和减少填充压力时都增加了燃烧.
结论:
- 提供了首个人类证据,表明由于增加预负载,HFrEF中激发性心肺-MSNA反射增强.
- 突出了两个单个单元种群对HFrEF中这种反射的差异性贡献.
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