| Objective Traumatic brain injury (TBI) is one of the highest mortality and morbiditydiseases in the world. Sensory,motor,learning and memory dysfunction caused by TBInot only aggravate the physical and mental suffering to the patients,but also increasefinancial and emotional burden to the society and their families.Studies showed thathypobaric hypoxia preconditioning not only can reduce ischemia-reperfusion(I/R) andsevere hypoxia(SH) injury,but also has the effect of anti-depressant andanxiety.Compared with hypobaric hypoxia preconditioning,hypobaric hypoxiapostconditioning(HHP) can be conducted after TBI,which have a potential clinicalapplication prospect.In the present study,the TBI rat model was built by fluid percussionmethod to investigate the effect of intermittent hypobaric hypoxiapostconditioning(IHHP) on neurological function prognosis in TBI rats,so as to burrowinto IHHP from bench to bedside.Methods30adult male Wistar rats were randomly divided into sham group(n=8),fpigroup(n=11) and IHHP group(n=11).The moderate TBI rat model was made by themethod of fluid percussion injury(FPI) and rats in IHHP group were submitted toIHHP(360Torr,2h,3trails spaced at24h) starting3h after TBI.The learning andmemory ability,motor coordination,anxiety and depression-like behaviors and survivingneurons of ipsilateral hippocampus were evaluated by Morris watermaze(MWM),Rotatord test,Open-field test and hippocampus nissl stain respectly.All data are presented as mean±SEM.All analyses were performed using SPSS v19.0software,P values of <0.05was considered significant for all comparisons.Results Morris water maze:compared with sham and IHHP group,learning andmemory abilitiy of rats in fpi group were significantly decreased(F=4.2576,P<0.05),whereas no difference was observed between sham and IHHPgroup(P>0.05);Rotatord test:compared with sham group,motor coordination of rats inIHHP group were significantly decreased(F=4.335,P<0.05),whereas no difference wasobserved between sham and fpi group(P>0.05);Open-field test:compared with sham andIHHP group,rats in fpi group showed significant anxiety and depression-like behavioralchanges,whereas no difference was observed between sham and IHHP group;Nisslstain:no difference of surviving neurons in ipsilateral hippocampus CA1and CA3region was observed among three gourps at3d after FPI(P>0.05).There weresignificantly fewer surviving neurons of ipsilateral hippocampus CA1and CA3regionin fpi group than sham and IHHP group at24d after FPI(F=46.758,5.486,P<0.05).Conclusion TBI caused learning and memory impairment,anxiety and depression-likebehaviors and delayed neuron death in hippocampus.To our knowledge,dual effects ofIHHP on neurological function prognosis in adult male TBI rats is firstly found in thepresent study,it will attenuate the impairment of learning and memory,alleviate anxietyand depression-like behaviors and reduce delayed neuron death in hippocampus,but italso will impair motor coordination at the same time. |
