大鼠坐骨神经损伤后许旺细胞源神经营养因子表达的实验研究

目的 观察坐骨神经在正常和损伤后许旺细胞源神经营养因子的表达。方法 将75只SD大鼠坐骨神经地夹伤、切断、切断加缝合等，术后第5、7、14、30、60d取材，做常规免疫组织化学研究。结果 （1）正常坐骨神经和脊髓中许细胞源神经营养因子有较弱表达；（2）切断组坐骨神经近段术后第14d许旺细胞源神经营养因子表达最高，远段第7d最高，脊髓术后第5d最高；切断缝合组和夹伤组神经和脊髓部以术后第60d最高；（3）损伤侧灰质后角表达强于对照侧。结论 (1)许旺细胞源神经营养因子在正常神经和脊髓中有较弱表达;(2) 旺细胞源神经营养因子在坐骨神经不同损伤情况下表达不同，但都高于正常组；（3）许旺细胞对神经损伤后修复作用可能通过许旺细胞源神经营养因子实现。

Expression of Schwann cell derived n euro trophic factor after injuried of sciatic nerve of rats

Objective To investig ate the expression of Schwann cell derived fa ctor （SDNF） in normal or under the condi tion of different injuries on the sciati c nerves of rats. Methods Sevent y-five S D rats were divided into three groups ac cording to different injuri es including transection， transection fo llowed by epineurial suture， and crush. Ten normal rats were treated as control. T he immunohistochemistry of both sciatic nerve and spinal cord were performed at 5，7，14，30，60 days after operation respec tively. Result （1）lower levels o f SDNF were detected in normal sciatic nerve， t he whole white matter and the laminae Ⅲ～ Ⅴ of dorsal horn of spinal cord. （2）In g roup transection， the SDNF levels reache d a maxium at 14 days after operation in proxi mal segment， at 7 days in distal segment ， and at 5 days in spinal cord. There ap peared a highest expression in related t issue of both group crushing and group s uturing at 60 days after operation. （3）SD N F staining of dorsal horn ipsilateral to the nerve lesion was stronger than that of contralateral. There was a transient expression in spinal motor neurons ipsi lateral to nerve lesion at 5 days in gro up crushing and group transection and at 30 days in group suturing. Conclusi on （1）There is a weaker expression i n norma l sciatic nerve and spinal cord. （2）The expression of SDNF varies with the diffe rent nerve lesions. （3）Significant quant ities of SDNF are released from Schwann cells after nerve lesion， and SDNF is then available to the axon of the lesioned neurons which may promote neuro n repair.