In the mammalian adult hippocampus, new neurons are continuously generated throughout life in the subgranular zone of the dentate gyrus. Increasing evidence point out the contribution of adult-born hippocampal granule cells (GCs) to cognitive processes such as learning and memory, indicating the relevance of understanding the molecular mechanisms that control the development of these new neurons in the preexisting hippocampal circuits. Cell proliferation and functional integration of adult-born GCs is a process highly regulated by different intrinsic and extrinsic factors. In this review, we discuss recent advances related with cellular components and extrinsic signals of the hippocampal neurogenic niche that support and modulate neurogenesis under physiological conditions.

在哺乳动物的成年海马中，整个齿状回亚颗粒区的整个生命中不断产生新的神经元。越来越多的证据指出，成人出生的海马颗粒细胞（GCs）对认知过程（如学习和记忆）的贡献，表明了解控制现有海马回路中控制这些新神经元发育的分子机制的相关性。成年出生的GC的细胞增殖和功能整合是一个受不同的内在和外在因素高度调节的过程。在这篇综述中，我们讨论了在生理条件下支持和调节神经发生的海马神经源利基的细胞成分和外在信号相关的最新进展。