在患有充血性心力衰竭的患者中,对运动的慢性反应受损. postsynaptic β-adrenergic 脱敏化的作用
W S Colucci1, J P Ribeiro, M B Rocco
1Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115.
Circulation
|August 1, 1989
概括
患有充血性心力衰竭 (CHF) 的患者表现出对运动反应的心率 (HR) 减弱. 这很可能是由于β-上腺素受体敏感性降低,而不是改变了北上腺素水平.
科学领域:
- 心脏病学 心脏病学
- 运动生理学 运动生理学
- 药理学 药理学是指药理学的学科.
背景情况:
- 患有充血性心力衰竭 (CHF) 的患者在运动期间经常表现出衰弱的心率 (HR) 反应.
- 对于CHF中这种减少的运动HR反应的潜在生理机制尚未完全理解.
研究的目的:
- 调查心血管疾病患者减弱运动HR反应背后的机制.
- 确定交感神经系统活动和β-上腺素受体功能的作用.
主要方法:
- 在59名心血管疾病患者和46名正常受试者中比较了运动HR和北上腺素 (NE) 水平.
- 评估了对异二醇输注的HR反应,以及在CHF患者中milrinone的影响.
- 与峰值运动氧气消耗 (VO2) 相关的HR和NE反应.
主要成果:
- 慢性心血管疾病患者的峰值运动HR和HR增幅下降,与峰值VO2有很强的相关性.
- 峰值运动NE水平和增量在CHF患者中没有减弱.
- 运动HR与NE增加的比率,即节交感反应的指数,在CHF下降,与运动损伤相反相关.
结论:
- 在CHF中,HR对运动的减弱反应部分是由于 postsynaptic beta-adrenergic受体脱敏.
- 交感神经系统活动在休息时升高,但在CHF运动时不能充分增加HR.
- 针对β-上腺素路径的药理干预措施可以改善心血管衰竭患者的运动能力.
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