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Remodeling of integrated contractile tissues and its dependence on strain-rate amplitude.

ABSTRACT: Here we investigate the origin of relaxation times governing the mechanical response of an integrated contractile tissue to imposed cyclic changes of length. When strain-rate amplitude is held constant as frequency is varied, fast events are accounted for by actomyosin cross-bridge cycling, but slow events reveal relaxation processes associated with ongoing cytoskeletal length adaptation. Although both relaxation regimes are innately nonlinear, these regimes are unified and their positions along the frequency axis are set by the imposed strain-rate amplitude.

SUBMITTER: Oliver M

PROVIDER: S-EPMC3940190 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature

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Remodeling of integrated contractile tissues and its dependence on strain-rate amplitude.

Oliver Madavi M Kováts Tímea T Mijailovich Srboljub M SM Butler James P JP Fredberg Jeffrey J JJ Lenormand Guillaume G

Physical review letters 20101004 15

Here we investigate the origin of relaxation times governing the mechanical response of an integrated contractile tissue to imposed cyclic changes of length. When strain-rate amplitude is held constant as frequency is varied, fast events are accounted for by actomyosin cross-bridge cycling, but slow events reveal relaxation processes associated with ongoing cytoskeletal length adaptation. Although both relaxation regimes are innately nonlinear, these regimes are unified and their positions along ...[more]

PMID: 21230941

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