INJURY TO SKELETAL MUSCLES OF MICE BY FORCED LENGTHENING DURING CONTRACTIONS

摘要: Our purpose was to determine the amount of injury extensor digitorum longus (EDL) and anterior tibial (ATB) muscles mice from 1 h 30 days following passive shortening lengthening, contractions lengthening contractions. The shortening-lengthening cycle 600 ms duration repeated every 5 s for min. Contractions were produced during either or phase with stimulation at 100 Hz 300 ms. evaluated by decrease in number fibres a cross-section muscle maximum isometric tetanic force (P0). Passively shortened lengthened actively EDL ATB showed no evidence injury. At 3-5 after contractions, an inflammatory response. days, injured 65% that contralateral control muscle, whereas change observed muscles. By 3 presence myoblasts, myotubes central nuclei indicated regeneration fibres. One hour P0 decreased about 75% value, but recovered completely days. In contrast, 52 40% respectively value then both within h. For secondary 49% day 47% Each gradually not significantly different values