ABSTRACT
OBJECTIVE@#To set up a classification standard of mild and moderate traumatic brain injury, for the purpose of reliable data comparison derived from different laboratories.@*METHODS@#Traumatic brain injury (TBI) in rats was prepared by using a metallic pendulum-striker device. After injury, five variable parameters including the time of apnea and the areflexia, time of corneal reflex, external auditory canal stung reaction, body-righting reflex and needling reaction were determined and scored by using rat coma criterion. These data were judged and classified into mild and moderate head injury by brain patho-anatomy changes. Then the data were used to set up a multivariate discriminate equation.@*RESULTS@#The distinguished probability of mild and moderate TBI according to actual direct measured value and the criterion were 88.9% and 91.9%, respectively.@*CONCLUSION@#This method is able to classify mild and moderate TBI in rats.
Subject(s)
Animals , Male , Rats , Brain Injuries/pathology , Coma/etiology , Forensic Medicine , Rats, Sprague-DawleyABSTRACT
Objective To study the correlation between cognitive dysfunction and cholinergic neuron changes in basal forebrain(BFB)and brainstem reticular formation(BSRF)areas after brain con- cussion(BC)in rats.Methods Eighty-four Spragne-Dawley rats weighing 250-310g were used.The BC rat models were reproduced by a self-made simple pendulum impact device,then the rats were ran- domized into one control group and six experimental groups(1 day,2 day,4 day,8 day,16 day,and 24 day groups;n=12 in each group).A Morris Water Maze(MWM)test was used to assess learning and memory function of the rats.Cholinergic neurons in the BFB and BSRF were identified with choline acetyltransferase(CHAT)antibody and quantitated.Results Compared with the control group,the la- tency to find the platform in MWM was much longer on days 1-3 after BC,but there was no statistical difference on days 4-21 after BC.The cell number and the ChAT expression activity of cholinergic neu- rons in the BFB were obviously decreased after BC,and reached the lowest level at 8 days after BC,then increased gradually and nearly reached the normal level at 24 days.The ChAT expression activity in BSRF declined on the first 2 days after BC,then went up gradually,and reached the peak at the 24th day.Conclusion The spatial cognition deficit of BC rats can be detected by MWM in the early period (1-3 days after BC).There are significant changes in the number and ChAT expression activity in BFB and BSRF after BC.The change of cholinergic neurons may be correlated with cognitive deficits in BC rats.