Possible Mechanism of Blast-Induced Neuronal Damage in Hippocampus May Explain Cognitive Deficits

Traumatic brain injury due to blast exposure is quickly becoming the most frequently seen injury in today’s battlefields. Alterations in cognitive function, such as attention, memory, language and problem solving skills appear to occur as a result of blast-induced TBI. Furthermore, behavioral symptoms such as mood changes, depression, anxiety, impulsiveness and emotional outbursts are associated with blast-induced TBI (Okie et al, 2005). Observed overlaps between symptoms of post-traumatic stress disorder (PTSD) and TBI confound the differential diagnosis. Thus, soldiers with blast-induced TBI may be substantially under-diagnosed after exposure to blast waves. Animal models of blast-induced TBI are underdeveloped and there is a vital need for blast exposure biomarkers to help effectively diagnosis blast-induced TBI. In this study, we have investigated the mechanisms that underlie cognitive impairment of blast-induced neurotrauma. We have studied the cascade of neurochemical changes within the hippocampus of blast-exposed animals using ¹H-Magnetic Resonance Spectroscopy (¹HMRS). Furthermore, we examined changes in TBI protein markers using Western blotting and immunohistochemistry. Results suggest that exposure to blast waves has a significant effect on the hippocampus.