Hyakutake Toru, Tsutsumi Yuya, Miyoshi Yohei, Yasui Manabu, Mizuno Tomoki, Tateno Mizuki
Faculty of Engineering, Yokohama National University, 79-5 Hodogaya, Yokohama 240-8501, Japan.
Graduate School of Engineering Science, Yokohama National University, 79-5 Hodogaya, Yokohama 240-8501, Japan.
Micromachines (Basel). 2023 Jul 14;14(7):1421. doi: 10.3390/mi14071421.
This study investigated the partitioning characteristics of red blood cells (RBCs) within capillaries, with a specific focus on ladder structures observed near the end of the capillaries. In vitro experiments were conducted using microfluidic channels with a ladder structure model comprising six bifurcating channels that exhibited an anti-parallel flow configuration. The effects of various factors, such as the parent channel width, distance between branches, and hematocrit, on RBC partitioning in bifurcating channels were evaluated. A decrease in the parent channel width resulted in an increase in the heterogeneity in the hematocrit distribution and a bias in the fractional RBC flux. Additionally, variations in the distance between branches affected the RBC distribution, with smaller distances resulting in greater heterogeneity. The bias of the RBC distribution in the microchannel cross section had a major effect on the RBC partitioning characteristics. The influence of hematocrit variations on the RBC distribution was also investigated, with lower hematocrit values leading to a more pronounced bias in the RBC distribution. Overall, this study provides valuable insights into RBC distribution characteristics in capillary networks, contributing to our understanding of the physiological mechanisms of RBC phase separation in the microcirculatory system. These findings have implications for predicting oxygen heterogeneity in tissues and could aid in the study of diseases associated with impaired microcirculation.
本研究调查了红细胞（RBC）在毛细血管内的分配特性，特别关注在毛细血管末端附近观察到的阶梯结构。使用具有阶梯结构模型的微流控通道进行体外实验，该模型由六个呈现反平行流动配置的分叉通道组成。评估了各种因素，如母通道宽度、分支之间的距离和血细胞比容，对分叉通道中红细胞分配的影响。母通道宽度的减小导致血细胞比容分布的异质性增加以及红细胞通量分数的偏差。此外，分支之间距离的变化影响红细胞分布，距离越小异质性越大。微通道横截面中红细胞分布的偏差对红细胞分配特性有重大影响。还研究了血细胞比容变化对红细胞分布的影响，较低的血细胞比容值导致红细胞分布中更明显的偏差。总体而言，本研究为毛细血管网络中红细胞分布特性提供了有价值的见解，有助于我们理解微循环系统中红细胞相分离的生理机制。这些发现对预测组织中的氧异质性具有重要意义，并可能有助于研究与微循环受损相关的疾病。
