不同年龄大鼠坐骨神经损伤后脊髓中神经生长导向因子Slit-1及Robo-2受体的表达变化

目的观察不同年龄大鼠坐骨神经损伤后,轴突导向因子Slit-1及其Robo-2受体在脊髓中的表达,以探讨不同年龄大鼠外周神经损伤后再生神经具有靶向性差异的可能机制。方法老年、成年和幼年大鼠各20只,建立左侧坐骨神经横断、硅胶管桥接模型。通过免疫荧光染色观察Slit-1蛋白和Robo-2受体在腰段脊髓中表达的变化,计算其荧光强度值,并进行统计学分析。结果伤后2周和4周,3组大鼠脊髓前角Slit蛋白均有较高表达,但各组间无显著差异。伤后2周和4周各组Robo-2受体表达均升高,其中老年鼠脊髓前角Robo-2受体表达明显高于成年和幼年组,差异有统计学意义(P0.05)。结论大鼠坐骨神经损伤后能刺激脊髓前角Slit-1高表达,不同年龄大鼠脊髓组织中Robo-2受体表达的差异可能决定了Slit-1在再生神经中的靶向性调节作用。

The Expression of Slit-1 Protein and Robo-2 Receptor in Spinal Cord after Sciatic Nerve Injury in Rats of Different Ages

Aim To observe the characteristics of Slit-1 protein and its receptor Robo-2 expression in spinal cord after sciatic nerve injury in rats of different ages and further investigate the possible mechanism of guided difference in regenerated nerves after peripheral nerve injury in rats of different ages.Methods The sciatic nerve was transected and connected with silicon tubes in 20 rats of 3 age groups （young,adult,elder） respectively.The expressions of Slit-1 and Robo-2 in lumbar spinal cord were examined with immunofluorescent staining.And their density ofimmunofluorescence was calculated.Results The expression of Slit-1 increased remarkably at anterior horn of spinal cord in the three groups 2 and 4 weeks after injury,but there was no difference among the groups.The expression of Robo-2 receptor increased 2 and 4 weeks after injury in anterior horn of spinal cord at each group,among which the expression of Robo-2 in elder rats were more than those in the young and adult rats statistically.Conclusion Injury of peripheral nerve in rats of different ages can stimulate the expression of Slit-1.The targeted adjustment effects of Slit-1 in regenerated nerves depend on the different expression of Robo-2 in different age groups.