INSERM U1215, Neurocentre Magendie, Bordeaux, France.
Université de Bordeaux, Bordeaux, France.
Cereb Cortex. 2019 Jul 22;29(8):3527-3539. doi: 10.1093/cercor/bhy224.
In nonhuman mammals and in particular in rodents, most granule neurons of the dentate gyrus (DG) are generated during development and yet little is known about their properties compared with adult-born neurons. Although it is generally admitted that these populations are morphologically indistinguishable once mature, a detailed analysis of developmentally born neurons is lacking. Here, we used in vivo electroporation to label dentate granule cells (DGCs) generated in mouse embryos (E14.5) or in neonates (P0) and followed their morphological development up to 6 months after birth. By comparison with mature retrovirus-labeled DGCs born at weaning (P21) or young adult (P84) stages, we provide the evidence that perinatally born neurons, especially embryonically born cells, are morphologically distinct from later-born neurons and are thus easily distinguishable. In addition, our data indicate that semilunar and hilar GCs, 2 populations in ectopic location, are generated during the embryonic and the neonatal periods, respectively. Thus, our findings provide new insights into the development of the different populations of GCs in the DG and open new questions regarding their function in the brain.
在非人类哺乳动物中，特别是在啮齿类动物中，大多数齿状回（DG）的颗粒神经元在发育过程中产生，但与成年神经元相比，人们对它们的特性知之甚少。尽管人们普遍承认，这些群体一旦成熟在形态上是无法区分的，但对发育产生的神经元的详细分析却很缺乏。在这里，我们使用体内电穿孔来标记在小鼠胚胎（E14.5）或新生儿（P0）中产生的齿状回颗粒细胞（DGC），并在出生后 6 个月内跟踪它们的形态发育。与在断奶（P21）或年轻成年（P84）阶段由成熟逆转录病毒标记的 DGC 相比，我们提供的证据表明，围产期出生的神经元，特别是胚胎期出生的细胞，在形态上与后来出生的神经元明显不同，因此很容易区分。此外，我们的数据表明，半月形和门区 GC 是异位的 2 个细胞群，分别在胚胎期和新生儿期产生。因此，我们的发现为 DG 中不同 GC 群体的发育提供了新的见解，并为它们在大脑中的功能提出了新的问题。
