Vitamin E prophylaxis upregulate serotonin immunoreactivity in the white matter at 7 dpi. Serotonin IR was quantified in the white matter at 7 dpi in all four groups (Figure 7A). There was a diet-dependent upregulation of 5-HT-IR in uninjured rats (* p < 0.05, CTL SHAM, n = 5 vs. VIT E SHAM, n = 5) and injured rats (* p < 0.05, CTL INJ, n = 5 vs. VIT E INJ, n = 5) (Figure 7B). There was no difference between uninjured and injured rats in the control diet (p > 0.05, CTL SHAM, n = 5 vs. CTL INJ, n = 5) and between uninjured and injured rats in the vitamin E diet (p > 0.05, VIT E SHAM, n = 5 vs. VIT E INJ, n = 5). 5-HT (5-hydroxytryptamine), NF (neurofilament).