Colosetti P, Olsson T, Miyazono K, Funa K
Ludwig Institute for Cancer Research, Biomedical Center, Uppsala, Sweden.
Brain Res Bull. 1995;37(6):561-7. doi: 10.1016/0361-9230(95)00021-6.
Transforming growth factor-beta (TGF-beta) has been found to be abundantly and specifically expressed in the nervous system. However, the function of TGF-beta during nerve regeneration is still unknown. We have examined the expression of TGF-beta isoforms and the latent TGF-beta binding protein (LTBP) by immunohistochemistry in the rat facial nuclei after unilateral axotomy. An increased immunoreactivity for all the TGF-beta isoforms and the LTBP was observed in the facial nuclei of the injured side during the regeneration period examined until Day 24. These differences were tested statistically by nominal logistic regression analysis. When the intensity of the immunoreactivity in the injured side was compared to that of the contralateral side, significantly increasing differences were found for TGF-beta 2 (p < 0.003) and LTBP (p < 0.002). Strong immunostaining was detected in the neuronal perikarya and their axons. No clear immunoreactivity was seen in either microglia or astrocytes. The enhanced immunoreactivity was seen in the operated side already at Day 3, remaining at high level with some fluctuations until Day 12 or 24 after axotomy. These findings suggest that TGF-beta might play a functional role in the regeneration of motor neurons.
已发现转化生长因子-β（TGF-β）在神经系统中大量且特异性表达。然而，TGF-β在神经再生过程中的功能仍不清楚。我们通过免疫组织化学方法检测了单侧轴突切断后大鼠面神经核中TGF-β亚型和潜伏性TGF-β结合蛋白（LTBP）的表达。在所检测的直到第24天的再生期内，在损伤侧的面神经核中观察到所有TGF-β亚型和LTBP的免疫反应性增加。通过名义逻辑回归分析对这些差异进行了统计学检验。当将损伤侧的免疫反应强度与对侧进行比较时，发现TGF-β2（p < 0.003）和LTBP（p < 0.002）存在显著增加的差异。在神经元胞体及其轴突中检测到强免疫染色。在小胶质细胞或星形胶质细胞中均未观察到明显的免疫反应性。增强的免疫反应性在术后第3天即在手术侧可见，在轴突切断后直到第12天或24天一直保持在高水平并伴有一些波动。这些发现表明TGF-β可能在运动神经元再生中发挥功能性作用。
