中度高温症会影响大脑动态自我调节,但不会影响其方向敏感性
Mahmoudreza Taghizadeh1,2, Marc-Antoine Roy1,2, Shahrzad Soleimani Dehnavi1,2
1Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, QC, Canada.
Journal of applied physiology (Bethesda, Md. : 1985)
|February 19, 2026
概括
中度高温症通过降低血流缓冲能力,特别是在更高频率下,损害动态大脑自身调节 (dCA). 然而,它保留了大脑压力-流量关系的方向敏感性.
科学领域:
- 生理学 生理学 生理学
- 神经科学是一个神经科学.
- 心血管研究研究心血管研究
背景情况:
- 动态大脑自调节 (dCA) 对于在血压波动中保持稳定的大脑血流 (CBF) 至关重要.
- 全身高温症可以通过增加脑血管抵抗来改变CBF调节.
- 超热症对dCA的方向敏感性的影响尚不清楚.
研究的目的:
- 调查中度高温症对dCA及其方向灵敏性的影响.
- 为了确定高温症是否会在血压快速变化期间改变脑血管缓冲能力.
主要方法:
- 20名健康成年人接受了0.05赫兹和0.10赫兹的振荡下体负压 (OLBNP) 在常温和高温条件下.
- 转移函数分析 (TFA) 和定向灵敏度分析量化了dCA指标.
- 持续监测中脑动脉平均血速 (MCAvmean) 和平均动脉压 (MAP).
主要成果:
- 超热症损害了dCA,由增加的TFA连贯性,减少的TFA阶段和在0.10Hz时增加的TFA增益证明.
- 方向灵敏度分析显示,在高温下,在两个频率上都保留了方向模式 (%MCAvmeanT/%MAPT).
- 绝对的方向灵敏度 (∆MCAvmeanT/∆MAPT) 仅在0.10 Hz时观察到,没有显著的热效应.
结论:
- 中度高温减弱了大脑血管系统的动态缓冲能力,特别是在更高的频率下.
- 大脑压力-流量关系的固有方向灵敏性在中度高温症期间保持.
- 不同的调节机制可能控制大脑自我调节的动态和定向方面.
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