Li Ru-Bo, Guo Xiao-Chong, Liang Hong-Xia, Wang Fu-Yuan, Zhu Bao-Li
Department of Forensic Pathology, China Medical University School of Forensic Medicine, No. 92, Beier Road, Heping District, Shenyang, Liaoning Province 110001, PR China.
Leg Med (Tokyo). 2009 Apr;11 Suppl 1:S176-9. doi: 10.1016/j.legalmed.2009.02.029. Epub 2009 Mar 28.
To investigate the mechanism and to explore the applicability of MMP-3 (matrix metalloproteinase-3) to determine the age of brain contusion, expression of MMP-3 was studied by immunochemistry and Western blot techniques on model of brain contusion in rats. Brain contusion was performed by falling weight in adult male Sprague-Dawley rats after anesthetized with diethyl ether, then maintained with 2% pentobarbital sodium (30 mg/kg). Samples were collected at 6 and 12 h, 1, 3, 5, 7, 10 and 14 days after the contusion. Histopathological examination and immunostaining of MMP-3 were conducted using paraffin sections. Protein of MMP-3 bands was visualized by ECL kit in Western blot. Result showed that: No staining in control and sham operation group. The staining of MMP-3 positive appeared 6 h after contusion, and it becomes stronger 24 h after contusion, the staining reached the maximum at 5 days post-contusion, then it decrease, positive staining could still be observed at 14 days after contusion. No MMP-3 expression was detected in control and sham group by Western blot analysis. Brain contusion caused the appearance of a band of 45 ku molecular weight, which corresponds to an active form of MMP-3. Conclusions were drew that there is no expression of MMP-3 in normal brain, that the expression of MMP-3 appears 6h after TBI, and that there is a relationship between the expression of MMP-3 and the time course after TBI, and MMP-3 would be used as an indicator for estimating the age of traumatic brain contusion in forensic pathology.
为研究基质金属蛋白酶-3（MMP-3）用于判定脑挫伤时间的机制并探讨其适用性，采用免疫化学和蛋白质免疫印迹技术，对大鼠脑挫伤模型中MMP-3的表达进行研究。成年雄性Sprague-Dawley大鼠经乙醚麻醉后，用2%戊巴比妥钠（30mg/kg）维持麻醉，采用自由落体法制作脑挫伤模型。于伤后6、12小时及1、3、5、7、10、14天取材。采用石蜡切片进行组织病理学检查及MMP-3免疫染色。蛋白质免疫印迹法采用ECL试剂盒显示MMP-3条带的蛋白。结果显示：对照组和假手术组无染色。挫伤后6小时出现MMP-3阳性染色，伤后24小时染色增强，伤后5天染色达最强，随后减弱，伤后14天仍可观察到阳性染色。蛋白质免疫印迹分析显示对照组和假手术组未检测到MMP-3表达。脑挫伤导致出现一条45ku分子量的条带，对应于MMP-3的活性形式。结论：正常脑组织中无MMP-3表达；TBI后6小时出现MMP-3表达；MMP-3表达与TBI后的时间进程相关；MMP-3可作为法医病理学中判断外伤性脑挫伤时间的指标。
