FIG. 1.

Transient receptor potential melastatin 4 (Trpm4) is expressed diffusely throughout the hippocampus from 1.5 h to 8 weeks following diffuse traumatic brain injury (TBI). Representative light micrographs of hippocampi from (A) sham-injured rats or rats subject to a central fluid percussion injury (CFPI) and killed at (B) 1.5 h, (C) 3 h, (D) 6 h, (E) 1 day, (F) 1 week, (G) 4 weeks or (H) 8 weeks post-TBI (n = 2 animals/time-point). At 1.5 h post-CFPI expression of Trpm4 is restricted to the white matter of the hippocampal fissure. At 3 h post-injury Trpm4+ cells are observed diffusely distributed throughout the hippocampus; however, the expression within the hippocampal fissure is predominant. Inlaid boxes a, b, c, d, e, f, g, and h are higher magnification micrographs of regions indicated by the dashed squares within (A), (B), (C), (D), (E), (F), (G), and (H). Diffuse expression of Trpm4 throughout the hippocampus persists through 8 weeks post-injury. Scale bar (A), (B), (C), (D), (E), (F), (G), (H): 200 μm. Scale bar a, b, c, d, e, f, g, h: 100 μm.