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Dynamic Adaption of Vascular Morphology

The structure of vascular networks adapts continuously to meet changes in demand of the surrounding tissue. Most of the known vascular adaptation mechanisms are based on local reactions to local stimuli such as pressure and flow, which in turn reflects influence from the surrounding tissue. Here we...

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Detalles Bibliográficos
Autores principales: Okkels, Fridolin, Jacobsen, Jens Christian Brings
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Research Foundation 2012
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3462325/
https://www.ncbi.nlm.nih.gov/pubmed/23060814
http://dx.doi.org/10.3389/fphys.2012.00390
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author Okkels, Fridolin
Jacobsen, Jens Christian Brings
author_facet Okkels, Fridolin
Jacobsen, Jens Christian Brings
author_sort Okkels, Fridolin
collection PubMed
description The structure of vascular networks adapts continuously to meet changes in demand of the surrounding tissue. Most of the known vascular adaptation mechanisms are based on local reactions to local stimuli such as pressure and flow, which in turn reflects influence from the surrounding tissue. Here we present a simple two-dimensional model in which, as an alternative approach, the tissue is modeled as a porous medium with intervening sharply defined flow channels. Based on simple, physiologically realistic assumptions, flow-channel structure adapts so as to reach a configuration in which all parts of the tissue are supplied. A set of model parameters uniquely determine the model dynamics, and we have identified the region of the best-performing model parameters (a global optimum). This region is surrounded in parameter space by less optimal model parameter values, and this separation is characterized by steep gradients in the related fitness landscape. Hence it appears that the optimal set of parameters tends to localize close to critical transition zones. Consequently, while the optimal solution is stable for modest parameter perturbations, larger perturbations may cause a profound and permanent shift in systems characteristics. We suggest that the system is driven toward a critical state as a consequence of the ongoing parameter optimization, mimicking an evolutionary pressure on the system.
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spelling pubmed-34623252012-10-11 Dynamic Adaption of Vascular Morphology Okkels, Fridolin Jacobsen, Jens Christian Brings Front Physiol Physiology The structure of vascular networks adapts continuously to meet changes in demand of the surrounding tissue. Most of the known vascular adaptation mechanisms are based on local reactions to local stimuli such as pressure and flow, which in turn reflects influence from the surrounding tissue. Here we present a simple two-dimensional model in which, as an alternative approach, the tissue is modeled as a porous medium with intervening sharply defined flow channels. Based on simple, physiologically realistic assumptions, flow-channel structure adapts so as to reach a configuration in which all parts of the tissue are supplied. A set of model parameters uniquely determine the model dynamics, and we have identified the region of the best-performing model parameters (a global optimum). This region is surrounded in parameter space by less optimal model parameter values, and this separation is characterized by steep gradients in the related fitness landscape. Hence it appears that the optimal set of parameters tends to localize close to critical transition zones. Consequently, while the optimal solution is stable for modest parameter perturbations, larger perturbations may cause a profound and permanent shift in systems characteristics. We suggest that the system is driven toward a critical state as a consequence of the ongoing parameter optimization, mimicking an evolutionary pressure on the system. Frontiers Research Foundation 2012-10-02 /pmc/articles/PMC3462325/ /pubmed/23060814 http://dx.doi.org/10.3389/fphys.2012.00390 Text en Copyright © 2012 Okkels and Jacobsen. http://www.frontiersin.org/licenseagreement This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in other forums, provided the original authors and source are credited and subject to any copyright notices concerning any third-party graphics etc.
spellingShingle Physiology
Okkels, Fridolin
Jacobsen, Jens Christian Brings
Dynamic Adaption of Vascular Morphology
title Dynamic Adaption of Vascular Morphology
title_full Dynamic Adaption of Vascular Morphology
title_fullStr Dynamic Adaption of Vascular Morphology
title_full_unstemmed Dynamic Adaption of Vascular Morphology
title_short Dynamic Adaption of Vascular Morphology
title_sort dynamic adaption of vascular morphology
topic Physiology
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3462325/
https://www.ncbi.nlm.nih.gov/pubmed/23060814
http://dx.doi.org/10.3389/fphys.2012.00390
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