Corticospinal tract axonal ‘dying-back' is reduced in TNC–/– mice after spinal cord injury. Localization of corticospinal tract axons anterogradely labeled with fluoro-ruby (red) with respect to the center of the lesion (indicated by stars) as seen by immunolabeling of astrocytes by GFAP (green) in consecutive longitudinal sections of a (a) TNC+/+ and (b) TNC–/– mice 30 days after spinal cord injury. Tips of the longest axons of the corticospinal tracts are indicated by arrows. Bar = 100 µm. (c) Mean distances (±SEM) between the tips of the corticospinal tract axons and the lesion center in TNC–/– mice and TNC+/+ mice at 7, 14, and 30 days after injury (n = 4 for each time point). Broken lines indicate extent of the glial scar. Asterisk indicates a significant difference between the genotypes (P < 0.01, t-test). GFAP, glial fibrillary acidic protein; TNC, tenascin-C.