OBJECT: Mild, traumatic repetitive @entity542 (RHI) leads to @entity4934 and is associated with the early onset of @entity179 . The authors developed an animal model to investigate the behavioral and pathological changes associated with RHI. METHODS: Adult male C57BL/6 @entity19 were subjected to a single injury (43 @entity19 ), @entity130 (two injuries 24 hours apart; 49 @entity19 ), or no impact (36 @entity19 ). Cognitive function was assessed using the Morris water maze test, and neurological motor function was evaluated using a battery of neuroscore, rotarod, and rotating pole tests. The animals were also evaluated for cardiovascular changes, blood-brain barrier (BBB) breakdown, traumatic @entity21 , and neurodegenerative and histopathological changes between 1 day and 56 days after @entity131 . No @entity73 was detected in any group. The single-impact group showed mild impairment according to the neuroscore test at only 3 days postinjury, whereas RHI caused pronounced deficits at 3 days and 7 days following the second injury. Moreover, RHI led to functional impairment during the rotarod and rotating pole tests that was not observed in any animal after a single impact. Small areas of @entity1545 . observed after a single @entity1545 , were profoundly exacerbated after RHI. Immunohistochemical staining for @entity7001 revealed marked regional loss of immunoreactivity only in animals subjected to RHI. No deposits of beta-amyloid or tau were observed in any brain-injured animal. CONCLUSIONS: On the basis of their results, the authors suggest that the brain has an increased vulnerability to a second traumatic insult for at least 24 hours following an initial episode of mild @entity131 .

Mild XXXX increasing the brain's vulnerability to a second concussive impact.

@entity1545 :: ('MESH:D020214', 'Disease') :: ['cortical BBB breakdown and axonal injury', 'brain injury'] @entity131 :: ('MESH:D001930', 'Disease') :: ['brain trauma'] @entity19 :: ('10090', 'Species') :: ['mice'] @entity73 :: ('MESH:D003072', 'Disease') :: ['cognitive dysfunction'] @entity542 :: ('MESH:D006259', 'Disease') :: ['head injury'] @entity4934 :: ('MESH:D019954', 'Disease') :: ['neurobehavioral impairment'] @entity179 :: ('MESH:D019636', 'Disease') :: ['neurodegenerative disease'] @entity7001 :: ('17756(Tax:10090)', 'Gene') :: ['microtubule-associated protein-2'] @entity21 :: ('MESH:D001480', 'Disease') :: ['axonal injury'] @entity130 :: ('MESH:D014947', 'Disease') :: ['repetitive injury']
@entity542 :: (MESH:D006259,Disease) :: ['head injury']
