NGF、BDNF和NT-3在背根节卫星细胞的表达

目的：观察神经因子（NGF）、脑源性神经营养因子（BDNF）和神经营养因子－3（NF－3）及其mRNA在成年猫背根节（L6）卫星细胞的表达情况。方法：成的雄猫5只，随机取一侧的L6背根节（DRG）制作20μm厚冰冻切片，行免疫组化及原位杂交染色。观察NGF、BDNF和NT－3及其mRNA在DRG卫星细胞的分布以及亚细胞定位。结果：在正常DRG，可见NGF、BDNF和NT－3及其mRNA阳性卫星细胞。各因子mRNA的阳性反应物定位于胞质。BDNF－IR定位于胞质，而NGF－IR和NT－3－IR则定位于胞核。结论：背根节部分卫星细胞内有NGF、BDNF和NT－3及其mRNA的分布，BDNF和NGF、NT－3亚细胞定位的不同提示成年猫背根节卫星细胞内不同生长因子发挥作用的机制可能不同。

Expression of NGF, BDNF and NT-3 in Satellite Cells of Dorsal Root Ganglion

OBJECTIVE: To investigate the distribution of NGF, BDNF, NT-3 and their mRNA in satellite cells of dorsal root ganglion (DRG) in adult cat. METHODS: Five male adult cats were used and their L6 DRGs unilateral side were taken and sectioned into frozen sections 20 microm in thickness respectively. The sections were stained by immunohistochemistry ABC method (NGF antibody 1:1000, Sigma; BDNF antibody 1:500, Santa Cruz; NT-3 antibody 1:1500, Santa Cruz), and in situ hybridization study(cRNA probe 1:100). RESULTS: NGF, BDNF, NT-3 and their mRNA were observed in some satellite cells. The positive signal of mRNA for NGF, BDNF and NT-3 was observed in cytoplasm. However, there was difference in the subcellular localization of protein for the three factors. BDNF immunoreactivity (BDNF-IR) was located in cytoplasm, while NGF-IR and NT-3-IR were located in nucleus. CONCLUSION: The results demonstrated that some satellite cells contain NGF, BDNF and NT-3 as well as their mRNA. The difference of subcellular localization for NGF, BDNF and NT-3 indicated that the functional mechanism of each factor in satellite cells in adult cats may be different.