Sarcomere Stiffness during Stretching and Shortening of Rigor Skeletal Myofibrils.
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ABSTRACT:
SUBMITTER: Shalabi N
PROVIDER: S-EPMC5770557 | biostudies-literature | 2017 Dec
REPOSITORIES: biostudies-literature
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Sarcomere Stiffness during Stretching and Shortening of Rigor Skeletal Myofibrils.
Shalabi Nabil N Persson Malin M Månsson Alf A Vengallatore Srikar S Rassier Dilson E DE
Biophysical journal 20171201 12
In this study, we measured the stiffness of skeletal muscle myofibrils in rigor. Using a custom-built atomic force microscope, myofibrils were first placed in a rigor state then stretched and shortened at different displacements (0.1-0.3 μm per sarcomere) and nominal speeds (0.4 and 0.8 μm/s). During stretching, the myofibril stiffness was independent of both displacement and speed (average of 987 nN/μm). During shortening, the myofibril stiffness was independent of displacement, but dependent o ...[more]
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