Effect of GSNO on the expression of 3-NT determined by dot blot and IHC at 4 h after TBI and colocalization of 3-NT with vWF. Animals were treated with GSNO (50 μg/kg body weight) at 2 h after TBI. Dot blot (A) and its densitometric analysis (B), performed at 4 h after TBI, show the accumulation of 3-NT in the traumatic penumbra region. The expression of 3-NT was significantly reduced in the GSNO group. Photomicrographs of IHC of 3-NT (C), determined at 4 h after TBI, show the enhanced expression of 3-NT in and around vessels. Treatment with GSNO reduced the TBI-mediated increased expression of 3-NT. Colocalization of 3-NT with an endothelial cell marker vWF as yellowish fluorescence (D) indicates that 3-NT was expressed in endothelial cells. Dot blots (A, B) and photomicrographs (C, D) are representative of n = 3 in each group. Densitometry results (B) are expressed as fold change, and data are presented mean ± SD. *p < 0.05 vs. Sham and GSNO.