The Relation Between Capillary Transit Times and Hemoglobin Saturation Heterogeneity. Part 2: Capillary Networks.
The Relation Between Capillary Transit Times and Hemoglobin Saturation Heterogeneity. Part 2: Capillary Networks.
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DOI：
10.3389/fphys.2018.01296
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发表时间：
2018
影响因子：
4
通讯作者：
Jenny P
中科院分区：
文献类型：
--
作者：
Lücker A;Secomb TW;Barrett MJP;Weber B;Jenny P
大脑的新陈代谢高度依赖于持续的氧气供应。皮质微血管网络表现出不均匀的血流，导致组织氧合不均匀和毛细血管血红蛋白饱和。我们最近提出了毛细血管外流饱和异质性(COSH)来表示异质性对最易受缺氧影响的组织区域供氧的影响，并表明毛细血管内和毛细血管之间的扩散性氧交换(扩散相互作用)在简化的几何构型中显著降低了COSH。在这里，氧传输的数值模拟提出了从小鼠体感皮质衍生的毛细血管网络几何形状。扩散相互作用被发现与不包括扩散相互作用的模拟相比，COSH降低了41%到62%。穿过微血管网络的血红蛋白饱和度下降与红细胞通过时间密切相关，但饱和下降的变异系数大约低三分之一。出乎意料的是，毛细血管供应的组织圆柱体的半径与解剖组织圆柱体半径的相关性很弱，但与血红蛋白饱和度的相关性很强。因此，尽管毛细血管通过时间和红细胞压积分布不均，弥散相互作用对微循环实现组织氧合的能力有很大贡献。这些发现为了解脑部小血管疾病对组织氧合和脑功能的影响提供了洞察力。
Brain metabolism is highly dependent on continuous oxygen supply. Cortical microvascular networks exhibit heterogeneous blood flow, leading to non-uniform tissue oxygenation and capillary hemoglobin saturation. We recently proposed capillary outflow saturation heterogeneity (COSH) to represent effects of heterogeneity on oxygen supply to tissue regions most vulnerable to hypoxia, and showed that diffusive oxygen exchange among red blood cells within capillaries and among capillaries (diffusive interaction) significantly reduces COSH in simplified geometrical configurations. Here, numerical simulations of oxygen transport in capillary network geometries derived from mouse somatosensory cortex are presented. Diffusive interaction was found to reduce COSH by 41 to 62% compared to simulations where diffusive interaction was excluded. Hemoglobin saturation drop across the microvascular network is strongly correlated with red blood cell transit time, but the coefficient of variation of saturation drop is approximately one third lower. Unexpectedly, the radius of the tissue cylinder supplied by a capillary correlates weakly with the anatomical tissue cylinder radius, but strongly with hemoglobin saturation. Thus, diffusive interaction contributes greatly to the microcirculation's ability to achieve tissue oxygenation, despite heterogeneous capillary transit time and hematocrit distribution. These findings provide insight into the effects of cerebral small vessel disease on tissue oxygenation and brain function.
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影响因子：
1.2
作者：
Drew PJ;Blinder P;Cauwenberghs G;Shih AY;Kleinfeld D
通讯作者：
Kleinfeld D
DOI：
10.1073/pnas.2133652100
发表时间：
2003-10-28
影响因子：
11.1
作者：
Chaigneau, E;Oheim, M;Charpak, S
通讯作者：
Charpak, S
影响因子：
29
作者：
Machler, Philipp;Wyss, Matthias T.;Weber, Bruno
通讯作者：
Weber, Bruno
DOI：
10.1073/pnas.95.26.15741
发表时间：
1998-12-22
影响因子：
11.1
作者：
Kleinfeld, D;Mitra, PP;Denk, W
通讯作者：
Denk, W
影响因子：
25
作者：
Blinder, Pablo;Tsai, Philbert S.;Kaufhold, John P.;Knutsen, Per M.;Suhl, Harry;Kleinfeld, David
通讯作者：
Kleinfeld, David