Hevner Robert F, Neogi Tina, Englund Chris, Daza Ray A M, Fink Andy
Department of Pathology, University of Washington, Harborview Medical Center, Box 359630, 325 Ninth Ave, Seattle, WA 98104-2499, USA.
Brain Res Dev Brain Res. 2003 Mar 14;141(1-2):39-53. doi: 10.1016/s0165-3806(02)00641-7.
Cajal-Retzius cells are reelin-secreting neurons found in the marginal zone of the mammalian cortex during development. Recently, it has been proposed that Cajal-Retzius cells may be generated both early and late in corticogenesis, and may migrate into the cortex from proliferative zones in the subpallium (lateral ganglionic eminence and medial ganglionic eminence) or cortical hem. In the present study, we used reelin as a marker to study the properties of Cajal-Retzius cells, including their likely origins, neurotransmitters, and birthdates. In double labeling experiments, Cajal-Retzius cells (reelin(+)) expressed transcription factors characteristic of pallial neurons (Tbr1 and Emx2), contained high levels of glutamate, were usually calretinin(+), and were born early in corticogenesis, on embryonic days (E)10.5 and E11.5. Tbr1(+) cells in the marginal zone were almost always reelin(+). The first Cajal-Retzius cells (Tbr1(+)/reelin(+)) appeared in the preplate on E10.5. In contrast, interneurons expressed a subpallial transcription factor (Dlx), contained high levels of GABA, were frequently calbindin(+), and were born throughout corticogenesis (from E10.5 to E16.5). Interneurons (Dlx(+)) first appeared in the cortex on E12.5. Our results suggest that the marginal zone contains two main types of neurons: Cajal-Retzius cells derived from the pallium, and migrating interneurons derived from the subpallium.
卡哈尔-雷茨乌斯细胞是在发育过程中发现于哺乳动物皮质边缘区的分泌Reelin的神经元。最近，有人提出卡哈尔-雷茨乌斯细胞可能在皮质发生的早期和晚期都产生，并可能从皮质下增殖区（外侧神经节隆起和内侧神经节隆起）或皮质下半球迁移到皮质。在本研究中，我们使用Reelin作为标记来研究卡哈尔-雷茨乌斯细胞的特性，包括它们可能的起源、神经递质和出生日期。在双重标记实验中，卡哈尔-雷茨乌斯细胞（Reelin(+)）表达皮质神经元特有的转录因子（Tbr1和Emx2），含有高水平的谷氨酸，通常为钙视网膜蛋白(+)，并且在皮质发生的早期，即胚胎第（E）10.5天和E11.5天产生。边缘区的Tbr1(+)细胞几乎总是Reelin(+)。第一批卡哈尔-雷茨乌斯细胞（Tbr1(+)/Reelin(+)）在E10.5天出现在前板中。相比之下，中间神经元表达皮质下转录因子（Dlx），含有高水平的GABA，经常为钙结合蛋白(+)，并且在整个皮质发生过程中产生（从E10.5天到E16.5天）。中间神经元（Dlx(+)）在E12.5天首次出现在皮质中。我们的结果表明，边缘区包含两种主要类型的神经元：源自皮质的卡哈尔-雷茨乌斯细胞和源自皮质下的迁移中间神经元。
