标志着血红蛋白质量膨胀和血体积收缩在夏尔巴人适应到5400米的海拔高度
Johanna Roche1, Santosh Baniya2, Suraj Bhatta3
1Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy.
Journal of applied physiology (Bethesda, Md. : 1985)
|November 7, 2024
概括
谢尔帕人和低地人的高海拔适应表现出类似的血液学反应. 在长时间暴露在5400米后,两组均经历了血体积减少和血红蛋白质量增加,这表明适应性没有根本差异.
科学领域:
- 人体生理学 人体生理学
- 高海拔适应 高海拔适应
- 血液学 血液学 血液学
背景情况:
- 低地人适应高海拔 (HA) 通常会降低血体积 (PV) 并增加血红蛋白质量 (Hb).
- 在HA的西藏高地人通常具有与海平低地人相似的血红蛋白度 ([Hb]),促使对他们的PV和Hb质量反应进行调查.
- 谢尔帕人是尼泊尔的藏族族群,他们被研究,以比较他们的血液学适应HA与本地低地人的血液学适应.
研究的目的:
- 为了调查是否血液对高海拔的反应在谢尔帕和本土低地人之间有所不同.
- 为了比较血体积 (PV) 和总血红蛋白质量 (Hb质量) 在5400米的适应过程中在两组中发生的变化.
主要方法:
- 在低海拔 (∼1,400 m) 和珠穆朗玛峰基地营 (EBC) (5,400 m) 经过∼2天 (EBC 1) 和∼6周 (EBC 2) 后,使用一氧化碳再呼吸来测量PV和Hb质量.
- 还测量了血红蛋白度 ([Hb]) 和循环中的红蛋白水平.
- 谢尔巴人与低地人之间的比较是在高海拔暴露期间的不同时间点进行的.
主要成果:
- 最初 (EBC 1),低地人显示[Hb]的增加,但夏尔巴人没有;然而,这两组都增加了红素,PV或Hb质量没有显著变化.
- 经过长时间暴露 (EBC 2),两组都显示[Hb]显著增加,PV显著减少,Hb质量大增加,红色素水平升高.
- 重要的是,PV减少,Hb质量扩张和红质素增加的幅度在EBC 2的夏尔巴人和低地人之间没有显著差异.
结论:
- 对于长时间暴露在非常高的海拔 (5400米) 上的血液学适应性,在夏尔巴人和本地低地人之间并没有根本的差异.
- 尽管在[Hb]反应中存在潜在的初始差异,但夏尔巴人和低地人表现出类似的血体积和血红蛋白质量的生理调整.
- 这些发现表明,与适应低地人相比,夏尔巴人长期居住在高海拔地区可能不涉及独特的血液学机制.
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