FIG. 9.

Neurodegeneration and synaptophysin immunoreactivity in the hippocampus following concussive brain trauma. Shown are representative photomicrographs of Nissl-stained sections, demonstrating a lack of change in the cellularity in the granule cell layers of the dentate gyrus at 24 h (A) and 7 days (B) post-injury. Fluoro-Jade-B-positive cells were present in the hilus of the dentate gyrus at 24 h (C), but not at 7 days (D) post-injury. (E) Quantification of Fluoro-Jade-B-positive cells was performed as described in the methods section. All values are presented as mean±standard deviation (*p<0.001 compared to sham animals; #p<0.01 compared to 3 or 7 days post-injury). Synaptophysin immunoreactivity was visualized as the classic trilaminar pattern of dark-light-dark staining in the molecular layer of the dentate gyrus in both sham-injured (F) and brain-injured animals at 24 h (G) and 14 days (H) post-injury (scale bar=100 μm for all panels).