人工重力,温度和缺氧对血液动力学反应和四肢血流的综合影响
Jason T Fisher1,2, Urša Ciuha1, Pierre Denise3
1Department of Automatics, Biocybernetics and Robotics, Jožef Stefan Institute, Jamova 39, 1000, Ljubljana, Slovenia.
European journal of applied physiology
|April 2, 2025
概括
人类对人造引力的耐受性在较高的温度和缺氧下降,影响心血管稳定性和血流调节. 这些联合的压力因素,特别是2G,挑战了身体维持平衡的能力,导致耐受性降低.
科学领域:
- 人类生理学 人类生理学
- 调节心血管系统的调节
- 环境压力反应环境压力反应
背景情况:
- 综合性心血管反应在环境和引力压力下保持平衡.
- 气体调节和温度调节的作用对于血管稳定至关重要.
- 在高重力下,温度和缺氧对这些系统的联合影响尚未完全理解.
研究的目的:
- 在高引力矢量下研究温度和缺氧之间的相互作用.
- 在被动离心过程中检查心血管和温度调节反应.
- 评估这些压力因素对人类耐受性的影响.
主要方法:
- 十名男性参与者进行了仰卧离心,以模拟1G和2G.
- 环境条件包括凉爽的 (18.4°C) 和温暖的 (29.1°C) 温度,正常氧和缺氧 (PIO2=92 mmHg).
- 监测了心血管 (HR,MAP,CO,SV,SkBF) 和温度调节 (皮肤/核心温度) 的反应.
主要成果:
- 在2G时,在温暖和低氧条件下,测试持续时间减少了16%.
- 2G显著增加了HR (29.3%) 和MAP (12.6%),并减少了SV (22.2%).
- 与凉爽的条件相比,温暖的条件降低了MAP (6.1%) 和SV (5.8%);手臂SkBF降低了Gz,而腿部SkBF增加了.
结论:
- 人类对被动离心器的耐受性在2G时显著降低,特别是在温暖和缺氧条件下.
- 升高的Gz和温暖的温度会损害血液动力学和腿部皮肤的血液流动反应,经常导致前同步症状.
- 手臂皮肤的血液流动是通过巴罗反射和温度调节调节的,而腿部皮肤的血液流动主要是通过巴罗反射调节的.
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