部分背根切断后备用DRG卫星细胞NGF、BDNF和NT-3的表达变化

为探讨部分去背根猫备用背根节 ( L6 )卫星细胞 NGF、BDNF和 NT-3的表达变化 ,将成年雄猫 2 0只分为正常对照组和术后 3 d、术后 7d及术后 10 d三个实验组。实验组行单侧部分背根切断术 (切除一侧 L1 ～ L5,L7～S2 DRG,保留 L6 背根为备用根 )。取正常组一侧和术后 3 d、7d及 10 d实验组手术侧的 L6 DRG制作 2 0μm厚冰冻切片 ,行免疫组化反应 ;观察 NGF、BDNF和 NT-3在 DRG卫星细胞的分布 ,计数各组 L6 DRG的 NGF、BDNF和 NT-3的阳性卫星细胞数量。结果发现 ,部分去背根术后7d和 10 d组 L6 DRG的 NGF、BDNF和 NT-3的阳性卫星细胞数量较术后 3 d组和正常组者明显增高 ( P<0 .0 1)。表明 ,单侧部分背根切断导致备用 DRG卫星细胞的 NGF、BDNF和 NT-3的表达上调 ,这一变化可能与脊髓可塑性有关。

THE EXPRESSION CHANGES OF NGF, BDNF AND NT-3 IN SATELLITE CELLS FOLLOWING PARTIAL DORSAL ROOT RHIZOTOMY

In order to investigate the expression changes of NGF, BDNF and NT-3 in satellite cells of dorsal root ganglion(DRG) following partial dorsal root rhizotomy, twenty male adult cats were used and divided into four groups. There groups of animals were performed unilateral partial dorsal root rhizotomy(L 1～L 5, L 7～S 2 DRG were sectioned, but L 6 was spared). The animals were sacrificed at survived 3, 7 and 10 days respectively after operation, and the L 6 DRG from the intact group and operated sides of three groups after operation was taken and sectioned into fronzen sections 20 μm in thickness respectively. The sections were stained by immunohistochemistry ABC method (NGF antibody 1∶3000, sigma; BDNF antibody 1∶500, Santa Cruz; NT-3 antibody 1∶1500, Santa Cruz). The numbers of satellite cells for NGF, BDNF and NT-3 in each group were counted and analyzed by statistic method. The results showed that the numbers of satellite cells for NGF, BDNF and NT-3 on 7 days and 10 days after operation increased more apparently than that of the intact group as well as 3 days group after operation(P<0.01). Our results provided the first evidence on the expression changes for NGF, BDNF and NT-3 in satellite cell following unilateral partial dorsal root rhizotomy. But the detailed functional complication for this change keeps being resolved.