Data from: Analytical modeling of the feto-placental vasculature system of the placenta: consideration of oxygen transport

The placenta is a transient vascular organ that enables nutrients and blood gases to be exchanged between fetal and maternal circulations. Herein, the structure and oxygen diffusion across the trophoblast membrane between the fetal and maternal red blood cells in the feto-placental vasculature system in both human and mouse placentas are present together as a functional unit. Previous models have claimed that the most efficient fetal blood flow relies upon structures containing a number of ‘conductive’ symmetrical branches, offering a path of minimal resistance that maximizes blood flow to the terminal villi, where oxygen diffusion occurs. However, most of these models have disregarded the actual descriptions of the exchange at the level of the intermediate and terminal villi. We are proposing a ‘mixed model’ whereby both ‘conductive’ and ‘terminal’ villi are presumed to be present at the end of single (in human) or multiple (in mouse) pregnancies. We predict an optimal number of 18 and 22 bifurcation levels in the human and the mouse placentas, respectively. Wherever possible, we have compared our model’s predictions with experimental results reported in the literature and found close agreement between them.胎盘（placenta）是一类暂时性血管器官，可介导胎儿与母体循环系统间的营养物质与血气交换。本文中，人类与小鼠胎盘的胎儿-胎盘血管系统（feto-placental vasculature system）内，胎儿与母体红细胞间的滋养层膜（trophoblast membrane）结构及其氧扩散过程，以功能单元的形式一并呈现。既往研究模型提出，高效的胎儿血流依赖于包含若干传导性（conductive）对称分支的结构：此类分支可提供最小阻力通路，最大化流向发生氧扩散的终末绒毛（terminal villi）的血流量。然而，多数此类模型均忽略了中间绒毛（intermediate villi）与终末绒毛层面的实际物质交换过程描述。我们提出一种“混合模型”，该模型假定，在人类单胎妊娠与小鼠多胎妊娠的胎盘中，其末端同时存在传导性与终末绒毛。我们预测，人类与小鼠胎盘的最佳分叉层级数分别为18级与22级。我们尽可能将本模型的预测结果与文献报道的实验结果进行对比，发现二者吻合度极高。