Department of Histology and Neurobiology, Dokkyo Medical University School of Medicine, Mibu, Tochigi 321-0293, Japan.
Neurosci Res. 2011 Aug;70(4):376-82. doi: 10.1016/j.neures.2011.05.005. Epub 2011 May 17.
To study the development of glutamatergic neurons during the main olfactory bulb morphogenesis in rats, we examined the expression of vesicular glutamate transporters 1 (VGLUT1) and 2 (VGLUT2). On VGLUT1, expressions of mRNA and immunoreactivity were first detected in the mitral cell layer on embryonic day (E) 17.5 and E18.5, respectively, and persisted in the E20.5 olfactory bulb. Much earlier (on E12.5) than VGLUT1, expressions of VGLUT2 mRNA and/or immunoreactivity were found in the olfactory epithelium, migratory cells and telencephalon. On E14.5, the mRNA expression was also observed in the prospective bulbar region and vomeronasal organ, while immunoreactivity existed in migratory cells and growing fibers. Some fibers were observed in the deep telencephalic wall. From E16.5 onward, mRNA expression became gradually detectable in cells of the mitral cell layer with development. On E17.5, immunoreactivity was first found in fibers of the developing olfactory bulb and in some immature mitral cells from E18.5 to E20.5. The present study clarifies the expression of VGLUT2 precedent to VGLUT1 during olfactory bulb morphogenesis, suggesting differential contribution of the two VGLUT subtypes to glutamate-mediated embryonic events.
为了研究大鼠嗅球形态发生过程中谷氨酸能神经元的发育，我们检测了囊泡谷氨酸转运体 1（VGLUT1）和 2（VGLUT2）的表达。VGLUT1 的 mRNA 和免疫反应性分别于胚胎第 17.5 天（E）和第 18.5 天首次在僧帽细胞层中检测到，并在第 20.5 天的嗅球中持续存在。比 VGLUT1 早得多（在 E12.5 时），VGLUT2 的 mRNA 和/或免疫反应性在嗅上皮、迁移细胞和端脑中被发现。在 E14.5，也在未来的嗅球区和犁鼻器中观察到 mRNA 表达，而免疫反应性存在于迁移细胞和生长纤维中。一些纤维在深端脑壁中被观察到。从 E16.5 开始，随着发育，mRNA 表达在僧帽细胞层的细胞中逐渐可检测到。在 E17.5，免疫反应性首先在发育中的嗅球纤维和从 E18.5 到 E20.5 的一些未成熟的僧帽细胞中被发现。本研究阐明了在嗅球形态发生过程中 VGLUT2 先于 VGLUT1 的表达，提示两种 VGLUT 亚型对谷氨酸介导的胚胎事件有不同的贡献。
