Dye coupling and connexin expression by cortical radial glia in the early postnatal subventricular zone |
| |
Authors: | Andressa S. Freitas Anna L.R. Xavier Carla M. Furtado Cecilia Hedin‐Pereira Maira M. Fróes João R.L. Menezes |
| |
Affiliation: | 1. Programa de Anatomia and Programa de Ciências Morfológicas, Lab. Neuroanatomia Celular, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, RJ 21941‐590, Brazil;2. Instituto Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, RJ 21941‐590, Brazil |
| |
Abstract: | In this study, we have analyzed the specific contribution of the cortical radial glia (RG) for gap junctional communication (GJC) within the postnatal subventricular zone (SVZ). To specifically target RG as source of dye‐coupling in situ, we have developed a new technique that involves direct cell loading through the processes that reach the pial surface, with a mix of gap junction permeant (Lucifer yellow, LY) and nonpermeant (rhodamine‐conjugated dextran 3 KDa, RD) fluorochromes, the latter used as a marker for direct loaded cells. Tissue sections were analyzed for identification of directly loaded (LY+RD+) and coupled cells (LY+RD–) in the SVZ. Directly loaded cells were restricted to the region underlying the pial loading surface area. Coupled cells were distributed in a bistratified manner, along the outer dorsal surface of the SVZ and aligning the ventricle, leaving the SVZ core relatively free. Blocking GJC prior to pial loading greatly reduced dye coupling. Phenotypic analysis indicated that coupling by RG excludes neuroblasts and is mostly restricted to cells of glial lineage. Notwithstanding, no corresponding restriction to specific cell phenotype was found for two connexin isotypes, Cx43 and Cx45, in the postnatal SVZ. The extensive homocellular cell coupling by RG suggests an important role in the regulation of neurogenesis and functional compartmentalization of the postnatal SVZ. © 2012 Wiley Periodicals, Inc. Develop Neurobiol 2012 |
| |
Keywords: | astrocytes RMS neurogenesis carbocyanine gliogenesis |
|
|