Effect of Mild Traumatic Brain Injury on Behavioral Reactions and Neocortical Morphology in Rats.

The original weight-drop model was employed to examine the effect of mild traumatic brain injury (TBI) on behavioral phenotype and neocortical morphology in rats. The neurological examination of rats with moderate TBI revealed the focal symptoms corresponding to pronounced neurological disorders, whereas in rats after mild TBI, there were only minor coordination disorders. On day 7 after injury, the rats with mild TBI demonstrated enhanced anxiety assessed by conditioned passive avoidance response. The morphometric analysis of the brain tissues revealed narrowing of the capillaries and increased score of hyperchromic neocortical neurons, which attested to cerebral hypoxia. The manifestations of mild TBI in original rat model demonstrated a close similarity to the symptoms of TBI in humans.