臂丛神经根性撕脱伤后神经营养因子在脊髓及肌肉中表达的变化

目的：通过观测臂丛神经根性撕脱伤后脊髓前角运动神经元及肌肉组织内神经营养因子表达的变化。探讨臂丛神经撕脱伤后中枢运动神经元，靶器官的功能改变可能对神经再生产生的影响。方法：清洁级Wistar大鼠48只，随机分成正常对照组和损伤术后1天，1，4，8和12周共六组，损伤组均从前路造成臂丛颈5，6，7神经根性撕脱伤，按各组所示时间取脊髓及肌肉分别检测碱性成纤维细胞生长因子（bFGF)蛋白及mRNA，神经生长因子（NGF）蛋白的表达，并采用计算机图像分析系统对组织切片中bFGF蛋白及mRNA,NGF蛋白进行半定量分析，比较，结果：臂丛神经根性撕脱伤后，肱二头肌内NGF蛋白表达增高，1天时达到高峰，随后下降，3个月时仍高于对照组，而脊髓前角运动神经元bFGF蛋白及mRNA的表达在伤后亦升高，1周时达到高峰，随后下降，3个月时下降到稍低于正常水平，结论：臂丛神经根性撕脱伤后神经营养因子在中枢神经元及靶器官内表达增高，可能起保护神经元，促进神经再生的作用。

VARIATION OF NEUROTROPHIC FACTORS EXPRESSION IN SPINAL CORD AND MUSCLE AFTER ROOT AVULSION OF BRACHIAL PLEXUS

Objective To investigate the variation of neurotrophic factors expression in spinal cord and muscle after root avulsion of brachial plexus. Methods Forty-eight Wistar rats were involved in this study and according to the observing time in 1st day, 1st week, 4th week, 8th week, and 12th week after avulsion, and the control, were divided into 6 groups. By immunohistochemical and hybridization in situ assays, the expression of nerve growth factor (NGF) on muscle, basic fibroblast growth factor(bFGF) and its mRNA on the neurons of corresponding spinal cord was detected. Computer image analysis system was used to calculate the result. Results After the root avulsion of brachial plexus occurred, expression of NGF increased and reached to the peak at the 1st day. It subsided subsequently but was still higher than normal control until the 12th week. While expression of bFGF and its mRNA increased in the neurons of spinal cord and reached to the peak at the 1st week. Then it dropped down and at the 12th week it turned lower than normal control. Conclusion After root avulsion of brachial plexus, neurotrophic factors expression increase on target muscle and neurons of corresponding spinal cord. It maybe the autoregulation and may protect neuron and improve nerve regeneration.