联合应用神经营养素-4胶质细胞源性神经营养因子对脊髓前角运动神经元的保护作用研究

Protective effect of glial cell line-derived neurotrophic factor and NT-4 infused into the tube setted into cavitas subarachnoidealis on spinal front corner motor neurons

目的研究周围神经损伤后经蛛网膜下腔置管局部联合应用神经营养素(NT)-4和外源性胶质细胞源性神经营养因子(GDNF)对脊髓前角运动神经元的保护作用。方法成年SD大鼠随机分为3组,GDNF组、NT-4组和GDNF联合NT-4组。切断大鼠坐骨神经致相应脊髓前角运动神经元损伤,于第5、6腰椎椎间隙行蛛网膜下腔置管,并注入外源性GDNF(10μg/mL)和NT-4,不同时间处死动物并取材,对L4～6节段脊髓标本冰冻切片,行苏木素-伊红染色、尼氏体染色、胆碱酯酶染色。结果 GDNF联合NT-4组脊髓前角运动神经元的存活率、胆碱酯酶阳性颗粒面积均比前2组有明显提高,组间比较差异有统计学意义(P<0.05)。结论周围神经损伤后通过蛛网膜下腔联合注入NT-4、GDNF较两者单独使用更有利于保护脊髓运动神经元。

Objective To investigate the effect of exogenous glial cell line-derived neurotrophic factor（GDNF） and NT-4 infused into the cavitas subarachnoidealis on spinal front corner motor neurons after sciatic nerve axotomy.Method Seventy-two healthy SD rats were divided into 3 groups randomly： GDNF group,NT-4 group,GDNF and NT-4 group.The left sciatic nerve in rats were cut off and spinal cord anterior horn motor neurons were damaged.And then NT-4 and GDNF were injected into cavitas subarachnoidealis at L5-6 in groups,respectively.The rats were sacrificed on postoperative day 1,2,4,8 w respectively.Their specimen of L4-6 spinal cord were taken at different time and sectioned.The HE staining,Nissl staining and cholinesterase（ChE） staining in motor neurons were used for counting of motor neurons.Result In GDNF and NT-4 group the number of motor neurons in spinal front corner and the ChE activity were notable higher than that of other groups,whict had significant difference（P0.05）.Conclusion The exogenous GDNF and NT-4 infused into the cavitas subarachnoidealis were supposed to play a more important role in protecting the degenerated spinal motor neuron from death after sciatic nerve injury.