摘要
Objective To investigate the role of tyrosine kinase receptor C(TrkC),the receptor of neurotrophin-3(NT-3),in neuroplasticity following spinal cord injury(SCI).Methods Rats with cord transection were allowed to survive for 1,3,7 and 14 d post operation(dpo).TrkC expressions at lower thoracic levels of the spinal cord and in precentral gyrus of cerebral cortex were investigated.Results TrkC protein levels at both the site of injury(T10-T11) and the neighboring segments(T9 and T12) in the spinal cord decreased significantly at 1-7 dpo,followed by a rapid increase at 14 dpo.The temporal changes in TrkC mRNA expression level showed a similar pattern with that of TrkC protein.In addition,the levels of TrkC protein and mRNA at the site of injury(T10-T11) were significantly higher than those at the neighboring spinal segments(T9 and T12).Besides,the levels of TrkC protein and mRNA were higher at the rostral segment than at the caudal segment.However,in the motor cortex,TrkC protein was not detected and TrkC mRNA was expressed at a very low level.Conclusion These results suggest that TrkC may be involved in neuroplasticity after SCI.
目的研究神经营养因子3(neurotrophin-3, NT-3)的受体—酪氨酸激酶受体C(tyrosine kinase receptor C, TrkC)在脊髓损伤(spinal cord injury, SCI)后神经重塑中的作用。方法研究脊髓全横断损伤大鼠手术后第1、3、7和14 d时,低位胸髓节段和大脑中央前回TrkC的表达。结果损伤节段(T10-T11)双侧和临近节段(T9和T12)的TrkC蛋白水平在术后1-7 d显著下调,而在术后14 d快速增强。此外,TrkC mRNA表达水平的暂时性变化与TrkC蛋白的变化模式相似。TrkC蛋白和mRNA在损伤节段(T10-T11)的水平显著高于在临近节段(T9和T12)的水平。此外,TrkC蛋白和mRNA在吻侧节段的水平高于在尾侧节段的水平。与脊髓不同的是,运动皮层中并未检测到TrkC蛋白,并且TrkC mRNA的表达水平也很低。结论 TrkC可能与脊髓损伤后的神经功能重塑有关。
基金
supported by the grants from National Natural Science Foundation of China (No. U0632008)
the Key Project of Science and Technology Research Foundation of Guangdong Province,China (No. 2008A030201019,2007-05/06-7005206)
the Key Project of Science and Technology Research Foundation of Guangzhou municipality,China (No. 09B52120112,2008A1-E4011-6)
the Foundation for Medical and Scientific Technology Research of Guangdong Province,China (No. A2009293)