βIII tubulin-expressing neurons reveal enhanced neurogenesis in hippocampal and cortical structures after a contusion trauma in rats

Neurogenesis is not only restricted to embryonic development, but also occurs in adult mammalian brains, including human. In this study, evidence is provided, that neurogenesis is involved in the repair of hippocampal and cortical structures after CNS injury. Cortical contusion was induced in 8-week-old Wistar rats. This trauma resulted in a primary cortical lesion and ipsilateral distant remote hippocampal damage, involving primarily CA3-pyramidal cells. The progression of injury was followed over a time course of 7 days, using Nissl-staining and a monoclonal antibody against betaIII tubulin-a specific marker for neurogenic cells. Nissl staining showed a partial recovery of damaged cortical and hippocampal cells at day 7. This recovery was accompanied by an increase of neurogenic cells in these structures, particularly in the dentate gyrus and the neocortical areas. Taken together, these findings provide evidence for the involvement of neurogenesis in the repair processes after traumatic brain injury.