红细胞的形状,方向和包装的变化是视网膜毛细血管大小的函数
Phillip Bedggood1, Yifu Ding1, Andrew Metha1
1Department of Optometry and Vision Sciences, The University of Melbourne, 3010, Australia.
Biomedical optics express
|February 26, 2024
概括
红细胞变形通过狭窄的视网膜毛细血管. 较窄的血管会导致细胞延长,与流量同步,并减少体积,这表明通过很困难.
科学领域:
- 眼科医生 眼科 眼科
- 生物物理学的生物物理.
- 血液学 血液学 血液学
背景情况:
- 红细胞 (RBC) 变形对于导航狭窄的毛细血管至关重要,特别是在中枢神经系统.
- 由于成像方面的挑战,人体毛细血管内的体内红细胞变形动态仍然不太清楚.
研究的目的:
- 在狭窄的视网膜毛细血管内,以非侵入式的方式研究红细胞变形和体内行为.
- 量化RBC体积,表面积,方向和间距相对于毛细血管直径.
主要方法:
- 使用高分辨率的自适应光学成像来追踪健康人体视网膜毛细血管 (直径≤8微米) 中的红细胞.
- 生成了平均红细胞的二维面部形状,假设圆形毛细血管截面,推断出三维形状.
- 双变线性模型分析了与血管直径相关的细胞行为.
主要成果:
- 观察到一个网络过效应:较窄的毛细血管含有较小的红细胞 (按表面积计算).
- 在较窄的容器中,RBC与流量重定向,延长,间距增加和体积减少,表明水喷射.
- 细胞定向和分离的双相分布在5μm以下出现,这表明流动的临界点.
结论:
- 红细胞表现出显著的变形和体积变化,表明通过视网膜毛细血管的通道发生在不情愿的情况下.
- 在狭窄的毛细血管 (<5μm) 中观察到的临界点可以优化流量对直径的灵敏度.
- 进化压力可能有利于比红细胞更窄的毛细血管光度,以尽量减少氧气交换和反应性氧物种损伤.
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