Sjöberg J, Kanje M
Department of Zoophysiology, University of Lund, Sweden.
Brain Res. 1989 Apr 17;485(1):102-8. doi: 10.1016/0006-8993(89)90671-9.
The effect of insulin-like growth factor (IGF-1) on the ability of the rat sciatic nerve to regenerate into a freeze-injured nerve segment was investigated. The freeze-injured segment was perfused for 6 days with Ringer solution and different concentrations of IGF-1, dispensed by a subcutaneously implanted osmotic minipump. At a pump concentration of 50, 100 and 200 micrograms IGF-1/ml the regeneration length increased with 14, 25 and 26%, respectively, as measured by the pinch test and by immunocytochemical staining for neurofilaments (NF) in the growing neurites. Schwann cells invading the freeze-injured segment were visualized by immunostaining for S-100 protein. In nerves perfused with Ringer solution alone the Schwann cells were present as far as the neurites had regenerated, while neurites seemed to grow slightly ahead of the Schwann cells in the nerves perfused with IGF-1. Incorporation of [3H]thymidine increased in IGF-1-treated nerves. However, IGF-1 perfusion did not increase thymidine incorporation when outgrowth of neurites was detained by a transection proximal to the freeze-injured area. The results suggest that IGF-1 affects regeneration by local stimulation of the growing neurites and that IGF-1 stimulates the proliferation of non-neuronal cells indirectly.
研究了胰岛素样生长因子（IGF-1）对大鼠坐骨神经再生进入冷冻损伤神经节段能力的影响。通过皮下植入的渗透微型泵，用林格溶液和不同浓度的IGF-1对冷冻损伤节段进行6天的灌注。在泵浓度为50、100和200微克IGF-1/毫升时，通过捏压试验和对生长神经突中神经丝（NF）的免疫细胞化学染色测量，再生长度分别增加了14%、25%和26%。通过对S-100蛋白的免疫染色观察侵入冷冻损伤节段的施万细胞。在仅用林格溶液灌注的神经中，施万细胞存在于神经突再生的部位，而在灌注IGF-1的神经中，神经突似乎比施万细胞生长得略快。在IGF-1处理的神经中，[3H]胸腺嘧啶核苷的掺入增加。然而，当神经突的生长因冷冻损伤区域近端的横断而受阻时，IGF-1灌注并没有增加胸腺嘧啶核苷的掺入。结果表明，IGF-1通过局部刺激生长中的神经突影响再生，并且IGF-1间接刺激非神经元细胞的增殖。
