Upregulation of Ryk expression in rat dorsal root ganglia after peripheral nerve injury
Upregulation of Ryk expression in rat dorsal root ganglia after peripheral nerve injury
复制标题
周围神经损伤后大鼠背根神经节Ryk表达上调
DOI：
10.1016/j.brainresbull.2008.05.011
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发表时间：
2008-10-22
影响因子：
3.8
通讯作者：
Liu, Yaobo
中科院分区：
文献类型：
--
作者：
Li, Xin;Li, Yao-hua;Liu, Yaobo
为研究周围神经损伤后背根神经节（DRG）Ryk表达的变化，建立单侧坐骨神经损伤大鼠模型。采用免疫组化方法观察大鼠坐骨神经损伤后DRG神经元Ryk蛋白表达的变化。同时用半定量PCR方法检测Ryk mRNA的变化，发现在蛋白水平和mRNA水平上都有变化。单侧坐骨神经损伤后，同侧DRG细胞内Ryk表达明显增加。进一步的免疫共染色研究证实，Ryk免疫反应（Ryk-IR）细胞是DRG的NeuN免疫反应（NeuN-IR）神经元。坐骨神经损伤后，DRG神经元中Ryk免疫反应阳性神经元的数量在损伤后2周达到高峰，到损伤后3周逐渐减少。在神经损伤后的不同时期，观察并计数不同大小的Ryk免疫阳性神经元的比例。通过RT-PCR分析Ryk mRNA显示与免疫染色相同的诱导模式。Ryk mRNA在正常或对侧DRG中均不表达，但在损伤后1、2和3周在同侧DRG中表达。Ryk mRNA水平在损伤后1 ~ 2周略有升高，3周后下降。这些结果提示Ryk可能参与了周围神经损伤后的可塑性。这是一个新的功能，除了其众所周知的基本活动作为受体介导轴突的指导和生长。(c)2008年爱思唯尔公司All rights reserved.
To study changes of Ryk expression in dorsal root ganglia (DRG) after peripheral nerve injury, we set up an animal model of unilateral sciatic nerve lesioned rats. Changes of Ryk protein expression in DRG neurons after unilateral sciatic nerve injury were investigated by immunostaining. Changes of Ryk mRNA were also tested by semi-quantitative PCR concurrently, We found, both at the level of protein and mRNA. that Ryk could be induced in cells of ipsilateral DRG after unilateral sciatic nerve lesion. Further investigation by co-immunostaining confirmed that the Ryk-immunoreactive (Ryk-IR) cells were NeuN-immunoreactive (NeuN-IR) neurons of DRG. We also showed the pattern of Ryk induction in DRG neurons after sciatic nerve injury: the number of Ryk IR neurons peaked at 2 weeks post-lesion and decreased gradually by 3 weeks post-lesion. The proportions of different sized Ryk IR neurons were also observed and counted at various stages after nerve lesion. Analysis of Ryk mRNA by RT-PCR showed the same induction pattern as by immunostaining. Ryk mRNA was not expressed in normal or contralateral DRG, but was expressed 1, 2 and 3 weeks post-lesion in the ipsilateral DRG. Ryk mRNA levels increased slightly from 1 to 2 weeks, decreased then by 3 weeks post-lesion. These results indicate that Ryk might be involved in peripheral nerve plasticity after injury. This is a novel function apart from its well-known fundamental activity as a receptor mediating axon guidance and outgrowth. (c) 2008 Elsevier Inc. All rights reserved.