【摘要】 目的观察大鼠弥漫性轴突损伤(DAI)早期脑内各部位淀粉样前体蛋白(β-APP)表达的变化。方法应用瞬间旋转致伤装置使16只SD大鼠发生DAI,并于伤后3h、6h分批处死(每时间点8只),另取8只大鼠作为正常对照,在24h后处死。取各组大鼠脑标本进行免疫组织化学观察,检查损伤后早期不同时间皮质下白质、海马、胼胝体、脑干区域的病理学改变。各部位(胼胝体、海马、脑干)的切片在显微镜下(200倍)进行半定量分析。结果损伤后3h,大脑皮质下白质、胼胝体和脑干β-APP呈弱阳性表达;损伤后6h,轴突局部免疫反应阳性较前明显增强,范围增大,半定量分析显示,胼胝体、海马、脑干的免疫反应均强于3h组。结论β-APP在DAI早期(伤后3h)即有明确表达,并呈逐渐增强趋势,可作为DAI早期的标志物。更多还原

【Abstract】 s Objective To observe the changes in the expression of β-amyloid precursor protein (β-APP) in selected brain areas in early stage of diffuse axonal injury (DAI) in rats. Methods DAI was induced in SD rats by a self-made rotating injury device. 16 rats in injury group were sacrificed by decapitation at 3 hours and 6 hours post-trauma, while the other 8 rats in sham injury group were put to death after 24 hours. The samples of the rat brain were stained with β-APP for immunohistochemistry in order to detect the early stage pathological changes in subcortex white matter, hippocampus, corpus callosum and brain stem at different time points. Results The β-APP expression was positive at 3 hours and was particularly strong at 6 hours after injury. The results of semi-quantitative analysis showed a significant differentiation of 3 hours and 6 hours in the immuno-positive expression of brain stem, corpus callosum and hippocampus. Histological results demonstrated that DAI occurred in all rats of injury group. Conclusion β-APP is a kind of sensitive and useful immunochemical marker for early DAI diagnosis, and it indicates axonal lesion or breakage.更多还原