局部应用GDNF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 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应用外源性胶质细胞源性神经营养因子(glial cell linederived neurotrophic factor,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2组,GDNF组和生理盐水(NS)组各24只。切断大鼠坐骨神经致相应脊髓前角运动神经元损伤,于L5,6椎间隙行蛛网膜下腔置管,GDNF组注入外源性GDNF6μl(10μg/ml),NS组同法注6μl生理盐水。不同时间处死动物并取材,对L4-L6节段脊髓标本冰冻切片,行HE染色,尼氏体染色、胆碱酯酶染色。结果:GDNF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NS组有明显提高,两组差异有统计学意义(P<0.05)。结论:周围神经损伤后通过蛛网膜下腔注入外源性GDNF对相应的脊髓运动神经元有保护作用。

Objective：To investigate the effect of exogenous glial cell line-derived neurotrophie factor（GDNF） infused into the eavitas subaraehnoidealis on cornu anterius medullae spinalis motor neurons after sciatic nerve axotomy. Methods ： Fortyeight healthy SD rats were divided into 2 groups randomly：GDNF group and NS group. The left sciatic nerve in rats were cut off. And then 0.9% saline （6 μl） and GDNF solution （6 μl） were injected into cavitas subarachnoidealis at L4-L6 in NS group and GDNF group,respectively. The rats were sacrificed on postoperative 1,2,4 and 8 weeks respectively. Their specimen of L4-L6 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. Results： In GDNF group the number of motor neurons in cornu anterius medullae spinalis and the ChE activity were higher than that of NS group. Conclusion：The exogenous GDNF infused into the cavitas subaraehnoidealis are supposed to protect the degenerated spinal motor neuron from death after sciatic nerve injury.