Previous studies of sheep TBI models demonstrate that diffuse axonal injury is observed 4 h post-impact,8,9 and immunoreactivity for microtubule-associated protein 2 (MAP2), a marker of the neuronal cytoskeleton, is reduced 2 h post-impact.10 Therefore, we hypothesized that changes in cellular anatomy and inflammation could be present at the acute 3-h post-impact time point of our study, thus providing insights into the early pathological processes occurring in a large animal mTBI model. Here, MAP2 is linked to concussion.