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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...
Autores principales: | , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Frontiers Research Foundation
2012
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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. |
format | Online Article Text |
id | pubmed-3462325 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2012 |
publisher | Frontiers Research Foundation |
record_format | MEDLINE/PubMed |
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 |
work_keys_str_mv | AT okkelsfridolin dynamicadaptionofvascularmorphology AT jacobsenjenschristianbrings dynamicadaptionofvascularmorphology |