马尾神经压迫性损伤对大鼠骶髓神经营养因子-3表达的影响

目的：探讨马尾神经压迫性损伤后不同时间骶髓神经元中神经营养因子-3的表达变化。方法：复制马尾神经压迫性损伤模型。于术后不同时间（1、7、21 d）,将动物过量戊巴比妥钠麻醉,心脏灌注后取骶髓（S2-3）,固定及切片后,用兔抗NT-3抗体行免疫组化ABC法染色。观察并测量各组骶髓神经元NT-3的阳性神经元数。结果：NT-3免疫阳性反应产物主要在骶髓神经元胞浆着色。腹角的NT-3阳性神经元数在脊髓挤压伤后7 d组和21 d组较正常组和24 h组明显增高（P〈0.05）;背角的NT-3阳性神经元数从术后24 h至术后7 d进行性减少,而术后21 d时则增加并高过正常水平（P〈0.05）。结论：NT-3不仅参与脊髓的正常生理活动,而且可能与脊髓挤压伤的早期修复有关。

Effect of cauda equina compression on the expression of NT-3 of sacral cord in rats

Objective:To investigate the changes of the NT-3 expression in sacral cord with cauda equina compressed injury at the different times.Methods: Compressed cauda equina injury model of rat was established.One day,seven days and twenty-one days after operation,rats were anesthetized by overdose pentobarbital sodium.The sacral cord was obtained and fixed after cardiac perfusion,and 5 μm coronal sections were colored with the method of immunohistochemistry by using anti-rabbit NT-3 antibody.The number of NT-3 positive neurons was determined.Results:NT-3 positive products were mainly distributed in cytoplasm.The number of NT-3 positive neurons in the ventral horn in 7d group and 21d group after cauda equine injury was significantly increased compared with that of the normal group and 24 h group;the number of positive neurons in the dorsal horn was progressively decreased in 1d and 7d group,whereas the number of NT-3 positive neurons in 21d group was significantly higher than that of the normal group(P<0.05).Conclusion:NT-3 not only participats in the normal physiological function of spinal cord,but also may play a role in the early repairment of compressed spinal cord injury.