暴露于被动热和冷应激差异调节大脑血管-CO反应能力
Bethany D Skinner1, Rebekah A I Lucas1, Samuel J E Lucas1,2
1School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom.
Journal of applied physiology (Bethesda, Md. : 1985)
|November 16, 2023
概括
热应激会损害大脑血流调节,在低头时增加大脑血管-CO2反应能力. 寒冷压力具有相反的影响,而热压力则挑战大脑输液维护,可能导致昏等不良事件.
科学领域:
- 身体生理学 身体生理学
- 神经科学是一个神经科学.
- 环境医学 环境医学
背景情况:
- 温度调节显著影响生理过程,包括大脑血流 (CBF).
- 热应激对大脑血管-CO2响应的影响,这是维持大脑 perfusion 的关键因素,仍然不完全理解.
研究的目的:
- 为了研究和比较大脑血管-CO2响应在正常热,被动热应激和寒冷应激条件下.
- 为了确定热条件如何影响大脑调节血液流动的能力,以应对二氧化碳水平的变化.
主要方法:
- 十六名健康参与者在随机交叉设计中接受了常温,热应激和冷应激条件.
- 在中部和后部脑动脉 (MCAv,PCAv) 中测量脑血速度.
- 参与者接受了超 (5% CO2) 和低 (潮末CO2为30 mmHg) 的挑战,以评估脑血管-CO2反应能力和脑血管导电性 (CVC).
主要成果:
- 与寒冷压力相比,热应激期间对低头的脑血管-CO2反应显著增加.
- 与正常热相比,脑血管-CO2对高头的反应在热应激期间下降,在寒冷应激期间增加.
- 当通过CVC计算血压时,超膜反应在热条件下没有显著差异,但热应激仍然显示出更大的低膜反应.
结论:
- 被动热应激,与寒冷应激不同,显著挑战维持足够的大脑输液.
- 在热应激期间,大脑血管对低头的反应增加可能会降低大脑血管储备能力,可能导致等不良事件.
- perfusion 压力的热调节变化会影响脑血管反应,而热应激会对脑 perfusion 维持构成更大的风险.
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