Toba Y, Ajiki K, Horie M, Sango K, Kawano H
Department of Developmental Morphology, Tokyo Metropolitan Institute for Neuroscience, Fuchu, Japan.
J Neuroendocrinol. 2001 Aug;13(8):683-94. doi: 10.1046/j.1365-2826.2001.00685.x.
The spatiotemporal localization of calbindin D-28k (Calb), a calcium-binding protein, was examined immunohistochemically in the developing rat olfactory system with special reference to cell migration from the olfactory placode. Calb immunoreactivity was first detected at embryonic day 12 (E12) in a few cells just outside the olfactory epithelium, and at E13, Calb-immunoreactive cells were found scattered in the laminin-rich mesenchyme. By E14, Calb-immunoreactive cells had increased in number and were seen along the entire migratory route between the vomeronasal organ, a derivative of the medial olfactory pit, and the ventromedial surface of the telencephalic vesicle. Calb neurones were not seen in the olfactory epithelium, a derivative of the lateral olfactory pit. Although the distribution pattern of Calb-immunoreactive cells was similar to that of luteinizing hormone releasing hormone (LHRH)-producing neurones, which are known to originate in the vomeronasal organ and migrate into the forebrain, Calb and LHRH immunoreactivities were contained in separate neuronal populations. Calb-immunoreactive cells were localized along the vomeronasal nerves, identified by labelling the vomeronasal organ with the lipophilic dye, DiI, and strongly immunoreactive for neural cell adhesion molecule (NCAM). These data strongly suggest that, in addition to LHRH neurones, the rat vomeronasal organ generates Calb-immunoreactive neurones which migrate along the vomeronasal nerves to enter the forebrain. The final fate and functional importance of these cells remains to be determined.
采用免疫组织化学方法，特别针对源自嗅基板的细胞迁移，研究了钙结合蛋白钙结合蛋白D-28k（Calb）在发育中的大鼠嗅觉系统中的时空定位。在胚胎第12天（E12），首次在嗅上皮外的少数细胞中检测到Calb免疫反应性，在E13时，发现Calb免疫反应性细胞散在于富含层粘连蛋白的间充质中。到E14时，Calb免疫反应性细胞数量增加，并沿整个迁移路径分布，该路径位于犁鼻器（内侧嗅窝的衍生物）与端脑泡腹内侧表面之间。在外侧嗅窝衍生物嗅上皮中未见到Calb神经元。虽然Calb免疫反应性细胞的分布模式与已知起源于犁鼻器并迁移至前脑的促黄体生成激素释放激素（LHRH）产生神经元的分布模式相似，但Calb和LHRH免疫反应性存在于不同的神经元群体中。Calb免疫反应性细胞沿犁鼻神经定位，通过用亲脂性染料DiI标记犁鼻器鉴定，并对神经细胞粘附分子（NCAM）有强烈免疫反应性。这些数据有力地表明，除了LHRH神经元外，大鼠犁鼻器还产生Calb免疫反应性神经元，这些神经元沿犁鼻神经迁移进入前脑。这些细胞的最终命运和功能重要性仍有待确定。
