In situ hybridization of Patched1 mRNA indicates an upregulation of Patched1 in the injured outer cortex. 2, 6, and 24 are h post-injury. Patched1 expression in control (a, n=11; b, n=11; c, n=7) and injured (a’, n=12; b’, n=15, c’, n=7) cortical explants revealed by in situ hybridization after 2 h (a,a’), 6 h (b,b’), and 24 h (c,c’) in culture. Note relative upregulation of Patched1 after 6 h (b,b’). Control explants that were fixed in full media are shown in (d).