Figure 2.

Slide-mounted gastrocnemius sections from a control subject (A–C, G–I) and a Peripheral Artery Disease (PAD) subject (D–F, J–L) were labeled for fluorescence microscopy and captured with 20×, 40× and 100× objectives. In longitudinally sectioned control myofibers (A–C), desmin (green) exhibited a normal distribution along the Z-disks, seen as regular, horizontal striations of bright green labeling and representing a well-organized cytoskeletal network. In PAD myofibers (D–F), desmin was disorganized and seen as a more dense deposition along the Z-disks in some areas (arrowheads), where abnormal cross-links between adjacent Z-disks are evident, and dense accumulation along the walls of large vacuoles (filled arrows). In cross-sections of control myofibers (G–I), desmin exhibited a normal honeycomb appearance throughout the myofiber (100×), representing numerous myofibrils in cross-section, and a high concentration in the subsarcolemma region (20×, 40× and 100×) (filled arrows). In cross-sections of PAD myofibers (J–L), desmin exhibited an irregular honeycomb appearance seen as intense and uneven labeling along the boundaries of the myofibrils (100×) (line arrows) and extensive, irregular cytoplasmic aggregates (arrowheads).