Table of Contents Author Guidelines Submit a Manuscript
The Scientific World Journal
Volume 2013 (2013), Article ID 627240, 8 pages
http://dx.doi.org/10.1155/2013/627240
Research Article

Early Neural Cell Death Is an Extensive, Dynamic Process in the Embryonic Chick and Mouse Retina

13D Lab (Development, Differentiation, Degeneration), Department of Cellular and Molecular Medicine, Centro de Investigaciones Biológicas, CSIC, C/Ramiro de Maeztu 9, E-28040 Madrid, Spain
2Department of Anatomy, Cellular Biology and Zoology, Centro Universitario de Plasencia, Universidad de Extremadura, Av. Virgen del Puerto, E-10600 Plasencia, Spain
3Instituto de Salud Carlos III, C/Sinesio Delgado 4, E-28029 Madrid, Spain

Received 16 January 2013; Accepted 13 February 2013

Academic Editors: D. Alfandari, A. Aronheim, A. S. Balajee, H. M. Chamberlin, A. Dricu, B. Gupta, and A. Kastner

Copyright © 2013 Teresa Chavarría et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Orchestrated proliferation, differentiation, and cell death contribute to the generation of the complex cytoarchitecture of the central nervous system, including that of the neuroretina. However, few studies have comprehensively compared the spatiotemporal patterns of these 3 processes, or their relative magnitudes. We performed a parallel study in embryonic chick and mouse retinas, focusing on the period during which the first neurons, the retinal ganglion cells (RGCs), are generated. The combination of in vivo BrdU incorporation, immunolabeling of retinal whole mounts for BrdU and for the neuronal markers Islet1/2 and βIII-tubulin, and TUNEL allowed for precise cell scoring and determination the spatiotemporal patterns of cell proliferation, differentiation, and death. As predicted, proliferation preceded differentiation. Cell death and differentiation overlapped to a considerable extent, although the magnitude of cell death exceeded that of neuronal differentiation. Precise quantification of the population of recently born RGCs, identified by BrdU and βIII-tubulin double labeling, combined with cell death inhibition using a pan-caspase inhibitor, revealed that apoptosis decreased this population by half shortly after birth. Taken together, our findings provide important insight into the relevance of cell death in neurogenesis.