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Elastic Energy Storage and Radial Forces in the Myofilament Lattice Depend on Sarcomere Length
We most often consider muscle as a motor generating force in the direction of shortening, but less often consider its roles as a spring or a brake. Here we develop a fully three-dimensional spatially explicit model of muscle to isolate the locations of forces and energies that are difficult to separ...
Autores principales: | , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Public Library of Science
2012
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3499250/ https://www.ncbi.nlm.nih.gov/pubmed/23166482 http://dx.doi.org/10.1371/journal.pcbi.1002770 |
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author | Williams, C. David Regnier, Michael Daniel, Thomas L. |
author_facet | Williams, C. David Regnier, Michael Daniel, Thomas L. |
author_sort | Williams, C. David |
collection | PubMed |
description | We most often consider muscle as a motor generating force in the direction of shortening, but less often consider its roles as a spring or a brake. Here we develop a fully three-dimensional spatially explicit model of muscle to isolate the locations of forces and energies that are difficult to separate experimentally. We show the strain energy in the thick and thin filaments is less than one third the strain energy in attached cross-bridges. This result suggests the cross-bridges act as springs, storing energy within muscle in addition to generating the force which powers muscle. Comparing model estimates of energy consumed to elastic energy stored, we show that the ratio of these two properties changes with sarcomere length. The model predicts storage of a greater fraction of energy at short sarcomere lengths, suggesting a mechanism by which muscle function shifts as force production declines, from motor to spring. Additionally, we investigate the force that muscle produces in the radial or transverse direction, orthogonal to the direction of shortening. We confirm prior experimental estimates that place radial forces on the same order of magnitude as axial forces, although we find that radial forces and axial forces vary differently with changes in sarcomere length. |
format | Online Article Text |
id | pubmed-3499250 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2012 |
publisher | Public Library of Science |
record_format | MEDLINE/PubMed |
spelling | pubmed-34992502012-11-19 Elastic Energy Storage and Radial Forces in the Myofilament Lattice Depend on Sarcomere Length Williams, C. David Regnier, Michael Daniel, Thomas L. PLoS Comput Biol Research Article We most often consider muscle as a motor generating force in the direction of shortening, but less often consider its roles as a spring or a brake. Here we develop a fully three-dimensional spatially explicit model of muscle to isolate the locations of forces and energies that are difficult to separate experimentally. We show the strain energy in the thick and thin filaments is less than one third the strain energy in attached cross-bridges. This result suggests the cross-bridges act as springs, storing energy within muscle in addition to generating the force which powers muscle. Comparing model estimates of energy consumed to elastic energy stored, we show that the ratio of these two properties changes with sarcomere length. The model predicts storage of a greater fraction of energy at short sarcomere lengths, suggesting a mechanism by which muscle function shifts as force production declines, from motor to spring. Additionally, we investigate the force that muscle produces in the radial or transverse direction, orthogonal to the direction of shortening. We confirm prior experimental estimates that place radial forces on the same order of magnitude as axial forces, although we find that radial forces and axial forces vary differently with changes in sarcomere length. Public Library of Science 2012-11-15 /pmc/articles/PMC3499250/ /pubmed/23166482 http://dx.doi.org/10.1371/journal.pcbi.1002770 Text en © 2012 Williams et al http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited. |
spellingShingle | Research Article Williams, C. David Regnier, Michael Daniel, Thomas L. Elastic Energy Storage and Radial Forces in the Myofilament Lattice Depend on Sarcomere Length |
title | Elastic Energy Storage and Radial Forces in the Myofilament Lattice Depend on Sarcomere Length |
title_full | Elastic Energy Storage and Radial Forces in the Myofilament Lattice Depend on Sarcomere Length |
title_fullStr | Elastic Energy Storage and Radial Forces in the Myofilament Lattice Depend on Sarcomere Length |
title_full_unstemmed | Elastic Energy Storage and Radial Forces in the Myofilament Lattice Depend on Sarcomere Length |
title_short | Elastic Energy Storage and Radial Forces in the Myofilament Lattice Depend on Sarcomere Length |
title_sort | elastic energy storage and radial forces in the myofilament lattice depend on sarcomere length |
topic | Research Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3499250/ https://www.ncbi.nlm.nih.gov/pubmed/23166482 http://dx.doi.org/10.1371/journal.pcbi.1002770 |
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