Department of Pathobiology, University of Pennsylvania School of Veterinary Medicine, 3900 Delancey Street, Philadelphia, PA 19104, USA.
Vet Pathol. 2012 Jan;49(1):155-65. doi: 10.1177/0300985811414035. Epub 2011 Aug 8.
Over the past 20 years, the conception of brain development has radically changed from a fixed and limited hierarchical process to a more plastic and continuous one. Most surprising, the field has learned that postnatal neurogenesis is not just a seasonal phenomenon in songbirds but a process that occurs across species and seasons. Astrocytes, whose primary role in the central nervous system was thought to be strictly supportive, have emerged as a heterogeneous population, a subset of which is the neural stem cell. Postnatal neurogenesis persists in specialized niches within the rostral subventricular zone and hippocampal dentate gyrus and, for a limited period, within the white matter tracts and external granular layer of the cerebellum. These specialized microenvironments are influenced by factors in the blood, cerebrospinal fluid, and local extracellular matrix. This article reviews the current understanding of adult neurogenesis, which is conserved across many vertebrate species, underscoring the value of animal models in past and present studies of human neurogenesis and neurogenic disease.
在过去的 20 年中，脑发育的概念已经从一个固定和有限的层次过程，彻底转变为一个更加具有可塑性和连续性的过程。最令人惊讶的是，该领域已经了解到，产后神经发生不仅仅是鸣禽中的季节性现象，而是一个在不同物种和季节中发生的过程。星形胶质细胞，其在中枢神经系统中的主要作用被认为是严格支持性的，现在已经成为一个异质群体，其中一部分是神经干细胞。产后神经发生持续存在于嗅球下区和海马齿状回的特定龛位中，并且在有限的时间内，存在于小脑的白质束和外颗粒层中。这些特定的微环境受血液、脑脊液和局部细胞外基质中的因素影响。本文综述了对成年神经发生的现有认识，这种认识在许多脊椎动物物种中是保守的，强调了动物模型在过去和现在的人类神经发生和神经发生疾病研究中的价值。
