Effect Of Hypothermia On The Expressions Of Aβ In Patients With Severe Traumatic Brain Injury

Objective:There is very few A(3 in normal brain tissue, but its content may be greatly increased after TBI, this study is to detect concentration changes of Aβin cerebrospinal fluid at different times after TBI, Evaluate the rlationship between the function of mild hypothermia in clinical treatment and prognosis, estabish stable normothermia and mild hypothermia rat fluid percusstion brain injury models, compared with conventional treatment, further confirmed mild hypothermia has advantages, and reveal the mechanism for brain protection in clinical, provides the theory basis for the further research.Methods:The study includes two parts.Part one:sixty sTBI patients were random selected, All 60 patients who were hospitaled in the department of neurosurgery of the Affiliated Hospital of Chinese People's Armed Police Force from October 2009 to August 2010 with sTBI(GCS<8 points),which were randomly assigned into two groups,30 patients with mild hypothermia treatment (HT group), and 30 cases with routine treatment(NT group). Mild hypothermia was induced within 24 hours after TBI,and maintain the rectal temperature(RT) in (32-35)℃,The Aβconcentration level of CSF was measured by ELISA method at 1,3,5 and 7 day after TBI.Meantime, the intracranial pressure(ICP) were also measured and the prognosis was evaluated by Glasgow Outcome Scale after six months. The second part were selected 12 healthy, free diet feeding conditions SD rats. The adult male Sprague Dawley rats were randomly assigned to normal group(n=3), sham injury group(n= 3), TBI-mild hypothermia group (n=3) and TBI-normothermia group, The rats of TBI-mild hypothermia group received hypothermia intervention with ice-water bathing after TBI was induced though the lateral fluid percussion device. The brain temperature was adjusted to (32±2)℃and maintained for 6 h. The TBI-normothermia group underwent all surgical and anesthetic procedures except the hypothermia implement. The sham injury group underwent all surgical and anesthetic procedures except the TBI and hypothermia implement,the histopathological evaluation was performed with immune fluorescence staining and RT-PCR in three rats of every group at six hours post-TBI.Results:The first parts sugested:Compared with mild hypothermia group,the Aβin cerebrospinal fluid is significantly increased after 3 days post-trauma, the ICP value is lower, GOS score higher with good prognosis, the second part showed:normal group and sham group have no changes in Ap,however TBI-NT group showed significantly higher than HT group.Conclusion:TBI may induce some significant alternation of Aβ,while conventional treatment,take mild hypothermia in the patients with sTBI can lower ICP levels and improve the prognosis of patients, mild hypothermia could inhibit expressive change of Aβ,as a new biomarker, there is relationship between the dynamic changes and degree of TBI.