Characterization of gp91phox after traumatic brain injury (TBI) using western immunoblots. (A) Immunoblotting signals before and after TBI in wild-type (Wt) mice (left) and gp91phox-/- mice (right). (B) In Wt mice, gp91phox levels were significantly increased on day 1 and day 2 after TBI (*p < 0.05 relative to sham). Gp91phox levels on the ipsilateral side were greater than on the contralateral side on day 1 and day 2 after TBI (*p < 0.05). Each value is the mean ± SE (n = 3). Note that the intensity of each sample was quantified and corrected relative to the labeling control, actin. Increasing levels of gp91phox were not seen in gp91phox-/- mice.