Figure 4

Representative photomicrographs of GFAP for astrocytes (A-H) and Iba-1 for microglia (I-P) immunohistochemistry from the external capsule, internal capsule, corpus callosum, and fornix in P11 saline control animals (A, C, E, G for GFAP; I, K, M, O for Iba-1) and hydrocephalic animals (B, D, F, H for GFAP; J, L, N, P for Iba-1). For GFAP, despite the immaturity of the tissue, the hydrocephalic animals exhibit the same severe glial reaction observed in the P22/23 animals as evidenced by large intensely stained cell bodies and thick processes (B, straight arrows). For Iba-1, note the round intensely stained profiles that represent highly phagocytic microglial somata in the white matter of control animals. These profiles are increased in hydrocephalic animals at this age, but are not found in any 22 or 23-day old animals. Scale bar = 25 μm and cresyl violet counterstain for all panels.