脑损伤对大鼠脑组织GDNF表达的影响

Effect of Traumatic Brain Injury on Expressions of Glial Cell Line-derived Neurotrophic Factor in Brain Tissue of Rats

目的探讨大鼠闭合性颅脑损伤后脑组织中胶质细胞源性神经营养因子(GDNF)的表达情况。方法制备Marmarou's大鼠落体打击损伤模型,将大鼠随机分为正常对照组、手术对照组及损伤后1h组、2h组、4h组、8h组、12h组、24h组、48h组、72h组和5d组。制备组织芯片,采用免疫组化法检测大脑皮层、海马以及脑干中GDNF的表达情况。结果正常组、手术对照组中皮层、海马以及脑干中可见到GDNF低水平表达,损伤后2h,皮层GDNF的表达达到高峰,并且大量表达可持续至伤后5d;损伤后2h海马以及脑干中GDNF的表达亦达到高峰,72h降至正常水平。结论闭合性颅脑损伤后,大鼠大脑皮层、海马以及脑干中GDNF在早期即明显表达,皮层中GDNF大量表达更为持久。

Objective To investigate the effect of traumatic brain injury on the expressions of glial cell line-derived neurotrophic factor（GDNF） in brain tissue of rats.Methods Male Sprague-Dawley rats were divided into normal control,sham surgery and injury groups. The rats of injury groups were subjected to Marmarou＇s closed traumatic brain injury and then were subdivided into 1 h,2 h,4 h,8 h,12 h,24 h,48 h,72 h and 5 d subgroups according to the time elapsed after injury. The expressions of GDNF were studied with immunohistochemistry.Results In control group,mild expressions of GDNF were observed in cortex,hippocampus and brain stem of rats. The number of GDNF positive neurons reached the peak level at 2 h in cortex after injury,and lasted for 5 d. In hippocampus and brain stem,the number of that also reached the peak level at 2 h,and lasted for 72 h.Conclusion The expressions of GDNF increased significantly at the early time in cortex,hippocampus and brain stem of rats after injury. The significant expression of GDNF lasted longer in cortex.