TNF-α在单纯性脑震荡大鼠皮质中的表达变化

Changes of TNF-α in the Cortex of Rat Brain after Pure Cerebral Concussion

目的观察单纯性脑震荡(pure cerebral concussion,PCC)大鼠前额叶皮质(prefrontal cortex,PC)、颞叶皮质(temporal cortex,TC)和梨状皮质(piriform cortex,Pir)区炎症因子TNF-α(tumor necrosis factor-α,TNF-α)的表达和时程变化规律,探讨TNF-α与脑损伤之间的病理联系.方法采用"金属单摆闭合式脑损伤打击装置"制备PCC模型,随机分为伤后3 h、12 h、1 d、2 d、3 d、7 d 6个时间点的PCC损伤组(n=5),另设正常对照组(n=5).采用兔抗TNF-α进行免疫组织化学SP法染色,观察PCC组和正常对照组大鼠PC、TC和Pir脑区TNF-α的表达变化.结果正常对照组大鼠PC、TC和Pir内TNF-α免疫阳性表达很弱,损伤后TNF-α的阳性表达和阳性细胞的数量逐渐增加,3 d组达高峰,7 d组后有下降趋势,但仍高于正常组(P<0.05).结论 PCC损伤早期PC、TC和Pir中TNF-α的表达量出现明显变化,提示TNF-α参与了PCC致伤后的病理变化.

Objective To study the expression and variation of the Tumor Necrosis Factor- α （TNF- α ） in prefrontal cortex （PC） , temporal cortex （TC） and piriform cortex （Pir） after the pure cerebral concussion （PCC） and to explore the relationship between TNF-a and pathological changes after brain injury. Methods Under the waking condition, the PCC models of the rats were established by using a metallic pendulum-striker concussive device. The rats were randomly divided into 3 h, 12 h, 1 d, 2 d, 3 d and 7 d （n = 5） groups after injury. One normal group （n = 5） was used as the control. To observe the distribution and changes of TNF- α expression in the PC, TC and Pir between the PCC and the control group, the immunohistochemical （SP method） was used with anti-TNF-αmonoelonal antibody （a special marker labeled with TNF-α ）. Results The expression of TNF- a was weak in the control group. The expression of TNF- a and the number of the TNF- α -immunopositive cells increased gradually from 3 h to 3 d in the PC, TC and Pir after injury compared with the control group, and reached the peak at 3 d and then downward but still higher than the control group until 7 d （P 〈 0.05 ）. Conclusion The expression ofTNF- α changes in the PC, TC and Pir during the early stage of the braininjury, suggesting that TNF- α may be involved in the pathological changes after PCC.