Study On The Spatial Cognition Deficits And The Expression Changes Of Tyrosine Hydroxylase After Cerebral Concussion In Rats

Objective: To study the spatial cognition outcome of different injury level of cerebral concussion (CC) and the expression changes of tyrosine hydroxylase(TH) post injury , so as to understand the neurobiologic mechanisms of the spatial cognition deficits after cerebral concussion in rats.Methods: The CC animal model were duplicated by using a metallic pendulum striker concussive device. According to classification standard, the injured rats were divided into pure cerebral concussion (PCC) and complicated cerebral concussion(CCC), then further distributed CC rats into six groups(n=10 in each group) :that is the group of 1d, 2d, 4d, 8d, 16d, 24d postconcussion. One control group was used (n =10). Spatial learning and memory ability were assessed with Morris Water Maze(MWM) in 8d group(1-7d) , 16d group(8-14d) and 24d group(15-21d). Brain tyrosine hydroxylase (TH)level was measured by Western blotting technique with TH specific antibody after CC 1d, 2d, 4d, 8d, 16d and 24d. There were 8 intact rats acting as a control group.Results: Reduced latency on MWM was observed in PCC rats (p<0. 05. vs control) up to 3 days post injury and in CCC rats (p<0.05.vs control) up to 6 days and 10th-11thday post injury. During the 1^st-24^thday post-CC, the TH expression in the basal ganglia area and nucleus accumbens septi were significantly increased compared with the control (p<0. 05) after CC .Conclusions: 1.The different types of the spatial cognition deficits relate to the injury level of CC severity in rats. 2. There are significantly...