Quantifying the impact of tissue metabolism on solute transport in feto-placental microvascular networks
AuthorsErlich, Alexander; orcid: 0000-0002-2294-1894
Nye, Gareth A.; orcid: 0000-0003-4508-0406
Brownbill, Paul; orcid: 0000-0002-8328-7072
Jensen, Oliver E.; orcid: 0000-0003-0172-6578
Chernyavsky, Igor L.; orcid: 0000-0003-0284-9318
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AbstractThe primary exchange units in the human placenta are terminal villi, in which fetal capillary networks are surrounded by a thin layer of villous tissue, separating fetal from maternal blood. To understand how the complex spatial structure of villi influences their function, we use an image-based theoretical model to study the effect of tissue metabolism on the transport of solutes from maternal blood into the fetal circulation. For solute that is taken up under first-order kinetics, we show that the transition between flow-limited and diffusion-limited transport depends on two new dimensionless parameters defined in terms of key geometric quantities, with strong solute uptake promoting flow-limited transport conditions. We present a simple algebraic approximation for solute uptake rate as a function of flow conditions, metabolic rate and villous geometry. For oxygen, accounting for nonlinear kinetics using physiological parameter values, our model predicts that villous metabolism does not significantly impact oxygen transfer to fetal blood, although the partitioning of fluxes between the villous tissue and the capillary network depends strongly on the flow regime.
CitationInterface Focus, volume 9, issue 5, page 20190021
PublisherThe Royal Society
DescriptionFrom Crossref journal articles via Jisc Publications Router
History: epub 2019-08-16, issued 2019-08-16, ppub 2019-10-06
Funder: Medical Research Council; Grant(s): MR/N011538/1
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