2003 Volume 2 Issue 2 Pages 21-26
Immobilization using non-elastic tape and a plastic cast induced degeneration of muscle fiber in the mouse soleus muscle (Fig. 1). We call this degeneration by wave-like structure in this report. The incidence of the wave-like structure increased with disuse time. Actually, about 65% of muscle fibers formed the wave-like structure after 7 days of immobilization on average. It was confirmed by the TUNEL (Terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin Nick-End labeling) method that the nuclear DNA of the wave-like structure was not fragmented. Therefore, the relationship between the wave-like structure and segmental necrosis is not clear, because the nuclear DNA of the segmental necrosis part is fragmented (Oka et al. 1996). However, we propose that the wave-like structure is a sensitive marker of morphological change induced by disuse.