Fig. 6. Small myofibers and tissue heterogeneity in MT1-MMP-deficient skeletal muscle tissue. Transverse sections of quadricep muscles in 4 week-old wild-type (left column), and MT1-MMP-deficient mice (right column) were analyzed as follows: HE-staining (a,b), immunostaining using anti-ß-DG to visualize legible peripheral myofibers (c,d), elastica-van gieson staining (EVG; e,f), and reticulin silver impregnation (silver staining; g,h). Note that the MT1-MMP-deficiency caused myofiber heterogeneity in size and shape, and peripheral ECM accumulation. Some faintly hypertrophied fibers containing centrally located nuclei also exist (arrow heads). Bars, 200 µm.