Animal model for sport-related concussion; ICP and cognitive function

Abstract
We have recently developed and characterized a rat model of mild traumatic brain injury which simulates the concussive injuries frequently encountered by players in American professional football. To study the effect of multiple impacts to the head on intracranial pressure, cognitive function, and exploratory behavior. The model was employed to cause concussion. Intracranial pressure, cognitive function, and exploratory behavior were examined following the multiple impacts of a 50 or 100 g projectile at a velocity of 9.3 or 11.2 m/s to the helmet protected head. Intracranial pressure measured at 6 and 10 h, and 1, 2, 3, 5, and 7 days. It was maximally elevated 10 h after impact and returned to the control levels 7 days later. Morris Water Maze assessment, 48 h after impact, revealed impaired cognitive function. Open field testing 2-4 days and 1 and 2 weeks after impacts indicated consistently reduced spontaneous exploratory activity. Multiple impacts to the head raise intracranial pressure and impair cognitive function and exploratory activity in this animal model.