Figure 8.

TAI results in chronic neuronal atrophy, not neuronal loss. A–F, Representative images of YFP⁺ neurons (see arrowheads) at 28 d post-injury (B, D) immunostained for phospho-c-Jun (p-c-Jun) (C, E). Note the atrophic change within the YFP⁺/phospho-c-Jun⁺ neuronal population (B, C) when compared to the YFP⁺/phospho-c-Jun-negative population (D, E), which is demonstrated quantitatively in A. No significant loss of YFP⁺ pyramidal neurons was observed at any time point studied (1–28 d) (F). The significant increase in the total number of YFP⁺ neurons observed at 28 d post-injury when compared to all other groups likely reflects an increase in the expression of YFP as animals age. Lines indicate a significant difference (p < 0.05) between time points, and the asterisk (*) indicates a significant difference from sham (p < 0.001). Scale bar: (in E) B–E, 20 μm.