大鼠脑弥漫性轴索损伤后早期病理学的研究

A Study on Pathologic Changes in Early Stage of Diffuse Axonal Injury in Rats

目的:探讨大鼠脑弥漫性轴索损伤(DAI)后早期轴索病理学改变及c-Fos蛋白的变化,为DAI的早期法医病理学鉴定寻找新的依据.方法:参照Marmarou的打击负荷伤模型,建立大鼠DAI动物模型.运用神经纤维特殊染色法观察轴索的病理学改变,并运用免疫组化SABC法观察c-Fos的变化.结果:嗜银染色于打击后1 h即可观察到部分神经纤维不规则增粗、肿胀、少数断裂,6 h观察到轴突断端球形改变,24 h可见典型轴索收缩球.打击后15 min时,即可观察到c-Fos的表达,3 h达到高峰,24 h后仍可见一定量表达,表达呈弥漫性,以胼胝体、脑干最为明显.对照组未见阳性反应.结论:嗜银染色可以很好的观察DAI后轴索的病理学改变.c-Fos是脑弥漫性轴索损伤的灵敏指标,对于早期DAI的诊断具有一定的应用价值.

Objective： To explore the changes of c - Fos in early stage of diffuse axonal injury （DAI） in rats so as to find a new evidence for early forensic pathologic diagnosis of DAI. Methods： Based on Marmarou＇s impact/compression trauma model, the rat model of DAI was established, ImmunohistochemicalSABC method was used to observe the expression of c - Fos, combining special staining of neurol fibers to observe the changes of axons. Results： It was found that swollen and ruptured axon in brain stem at 1h, marked swelling of the axonal severe end at 6 h, axonal retraction ball at 24 h by silver staining after DAI. The expression of c - Fos could be detected at 15 min after injury, peaked at 3 h. The expression of c - Fos was found in wide range but significant in callus and brain stem. The control group showed negative staining. Conclusion： Silver staining is a good way to observe the changes of axons, c - Fos is a sensitive index to DAI and is helpful to diagnose early DAI.