Fig. 5
Regeneration aided by passive stretch after muscle damage induced by LC. Muscle stretch was performed in a single 15-min bout at 1 day after LC. Rats exposed to LC were divided into two groups according to whether they underwent stretch (LC-alone vs. LC+Stretch). A Photomicrographs of the TA muscle (a–d LC-alone; e–h LC+Stretch) obtained at various times after LC-induced injury (a, e 2 days, b, f 3 days, c, g 4 days, d, h 5 days). Green Myosin heavy chain-immunoreactive myofibers (dMHC-ir), red dystrophin-ir myofiber membrane, blue nuclei labeled with 4′,6-diamidino-2-phenylindole. Scale bar 50 μm. B Proportion of myofibers containing dystrophin-ir and dMHC-ir, with labeling (a–h) corresponding to those in A. Bin width: CSA of 400 μm2. C Proportion of myofibers with dMHC-ir. On the third and fourth days after LC-induced injury, there was significantly more dMHC-ir myofibers, indicating myofiber regeneration, in the LC+Stretch group than in the LC-alone group (***p < 0.001, Fisher’s exact probability test)