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A comprehensive constitutive theory is developed for the diaphragm. The theory can describe the mechanical properties of the diaphragm muscle in its passive and active states in a unified manner. It also describes the mechanical properties of the diaphragm under mechanical loads in arbitrary directions. The theoretical model involves seven material constants that represent the nonlinear elastic moduli and activation strains of the diaphragm muscle. The values of these material constants are determined by using in vitro experimental data, including that from shear loading experiments which are documented in this work for the first time.
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Anisotropic mechanosensitive pathways in the diaphragm and their implications in muscular dystrophies
The diaphragm is the "respiratory pump;" the muscle that generates pressure to allow ventilation. Diaphragm muscles play a vital function and thus are subjected to continuous mechanical loading. One of its peculiarities is the ability to generate distinct mechanical and biochemical responses depending on the direction through which the mechanical forces applied to it. Contractile forces originated from its contractile components are transmitted to other structural components of its muscle fibers and the surrounding connective tissue. The anisotropic mechanical properties of the diaphragm are translated into biochemical signals that are directionally mechanosensitive by mechanisms that appear to be unique to this muscle. Here, we reviewed the current state of knowledge on the biochemical pathways regulated by mechanical signals emphasizing their anisotropic behavior in the normal diaphragm and analyzed how they are affected in muscular dystrophies.
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- Award ID(s):
- 1714478
- PAR ID:
- 10048882
- Date Published:
- Journal Name:
- Journal of Muscle Research and Cell Motility
- ISSN:
- 0142-4319
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1007/s10974-017-9483-7
