Guéneau G, Privat A, Drouet J, Court L
Dev Neurosci. 1982;5(4):345-58. doi: 10.1159/000112694.
Cell genesis in the subgranular zone of the dentate gyrus of 2-month-old rabbits has been investigated. After incorporation of tritiated thymidine, electron microscopic autoradiography allowed description of the ultrastructure of the cells labelled and the progressive transformation of these cells into granular neurons to be followed. Quantitative evaluation of the time course of this transformation has been performed by light microscope autoradiography using 1-micrometer sections. Precursor cells, labelled initially with 3H-thymidine, were transformed after 5 days into early neuroblasts, these cells in turn giving rise to neurons some 8 days later. At the latest time period examined (42 days), 80% of the labelled cells were neurons; more than 10% remained as precursor cells. It is suspected that the latter may behave as reserve cells. Small numbers of glial cells, astrocytes, and microglia, scattered throughout the hilus of the dentate gyrus and the molecular layer, were found labelled, and it is possible that they arise from a different precusor pool. It is concluded that the subgranular zone functions as a secondary matrix for granule neurons of the dentate gyrus in young rabbits. These late-forming and apparently synaptically uncommitted neurons may be recruited during the development and refinement of postnatal behavioral substrates, by one or other of the dominant afferent systems.
对2月龄家兔齿状回颗粒下区的细胞发生进行了研究。掺入氚标记的胸腺嘧啶核苷后，电子显微镜放射自显影能够描述标记细胞的超微结构，并追踪这些细胞逐渐转变为颗粒神经元的过程。使用1微米切片通过光学显微镜放射自显影对这种转变的时间进程进行了定量评估。最初用3H-胸腺嘧啶核苷标记的前体细胞在5天后转变为早期成神经细胞，这些细胞在约8天后又产生神经元。在检查的最晚时间段（42天），80%的标记细胞为神经元；超过10%仍为前体细胞。怀疑后者可能作为储备细胞。在齿状回的门区和分子层中散在发现少量标记的胶质细胞、星形胶质细胞和小胶质细胞，它们可能起源于不同的前体细胞池。得出的结论是，颗粒下区作为幼兔齿状回颗粒神经元的次级基质发挥作用。这些后期形成且明显未形成突触联系的神经元可能在出生后行为基质的发育和完善过程中，由一种或另一种主要传入系统募集。
