大鼠弥漫性脑损伤后S100β表达与损伤时间关系

目的探讨大鼠弥漫性脑损伤后S100β在脑组织中不同部位的时间相关性表达,并以此为弥漫性脑损伤时间推断,生前伤和死后伤判断,早期诊断提供实验依据。方法运用免疫组织化学和图像分析技术,检测弥漫性脑损伤后30min和2,4,12,24h及3,7d,死后10min损伤,各组S100β在大脑皮质、海马、丘脑、脑干中神经胶质细胞的表达,并设立正常对照组。结果S100β阳性细胞个数及蛋白表达在皮质、海马、丘脑形成先增后降再升的曲线,即两次表达高峰,脑干表达变化不显著;在伤后2h,海马、丘脑S100β表达细胞个数和蛋白量开始增加,4h有显著增加,12h达到高峰值,皮质部位在4h达到高峰。伤后7d恢复正常值。结论弥漫性脑损伤后S100β在不同部位表达有不同规律性且有较好的时间相关性,可成为法医学脑损伤时间推断的一种有效指标。

Time-dependent Expression of Astroglial S100β Following Diffuse Brain Injury in Rats

OBJECTIVE: To investigate the dynamics of the induction of S100beta in different parts of rat brain following the diffuse brain injury. METHODS: Immunohistochemistry and auto-image analysis were to determine the expression of astroglial S100beta after diffuse brain injury in rats. Forty rats were distributed into groups according to injury time of 30min, and2,4,12,24h, and 3,6 d after diffuse brain injury, and normal rats as control. RESULTS: The number of S100beta positive cells in the four areas increased significantly followed by a decrease, and then a further increase. The expression of S100beta could be detected increasing in 2h, and increased significantly in 4h, and it reached apex 12h after DBI, and decreased gradually to the level less than normal 3d, and returned to normal 7d following injury. In the postmortem injury groups, there were no significant changes in anti-S100beta immunoreactivities in four areas of brain compared to the control group. CONCLUSION: The present study showed the time-dependent expression of S100beta is obvious following diffuse brain injury, and suggested S100beta be suitable as a marker for brain injury age determination.