title: Granule cells born in the adult rat hippocampus can regulate the expression of GABAergic markers.
abstract: The granule cells (GCs) of the dentate gyrus transiently express markers of the GABAergic phenotype early during development. However, GCs are generated throughout life, posing the question of whether the newborn neurons in the adult rodent recapitulate the development of the neurotransmitter phenotype of GCs generated during embryonic and early postnatal development. In this work we asked whether newborn GCs transiently express a GABAergic phenotype during their development in the adult rat. Using retroviral infection, we labeled dividing cells in the dorsal hippocampus with GFP, identified them as granule cells, and determined their expression of GABAergic markers at different developmental stages. We found that GFP-positive cells express Prox-1 and calbindin, identifying them as GCs. GABA or GAD(67) was expressed in 13% of GFP-positive cells at 7 dpi, in 16% at 10 dpi and in 20% at 15 dpi. At 30 dpi, however, no GFP-positive cell somata containing GABAergic markers were detected, but their mossy fiber boutons did contain GAD(67). Interestingly, developing GCs detected with doublecortin and PSA-NCAM in non-injected adult rats, did not express GABAergic markers, suggesting that retroviral injection/infection stimulates their transient expression. However, in non-injected rats, a number of mossy fiber boutons of newborn granule cells detected with PSA-NCAM did express GAD(67). Our findings reveal that developing GCs born in the adult are able to transiently up-regulate the expression of GABAergic markers to be detected in their soma in response to insults, while they constitutively express GAD(67) in their mossy fibers.
authors: Department of Physiology, Biophysics and Neurosciences, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional, Apartado Postal 14-740, Mexico 07000 D.F., Mexico.
authors: Erika
authors: E
authors: Lara
authors: Jesús Q
authors: JQ
authors: Beltrán
authors: José
authors: J
authors: Segovia
authors: Rafael
authors: R
authors: Gutiérrez
mesh_terms: D000818:Animals; D000831:Animals, Newborn / Q000235:genetics; D015415:Biomarkers / Q000378:metabolism; D064026:Calbindins; D002454:Cell Differentiation / Q000235:genetics; D003594:Cytoplasmic Granules / Q000235:genetics / Q000502:physiology* / Q000821:virology; D000089622:Doublecortin Domain Proteins; D000089662:Doublecortin Protein; D005786:Gene Expression Regulation / Q000502:physiology*; D049452:Green Fluorescent Proteins / Q000096:biosynthesis / Q000235:genetics; D057809:HEK293 Cells; D006624:Hippocampus / Q000166:cytology* / Q000196:embryology / Q000821:virology; D006801:Humans; D008297:Male; D008869:Microtubule-Associated Proteins / Q000235:genetics; D008979:Moloney murine leukemia virus / Q000235:genetics; D039842:Neural Cell Adhesion Molecule L1 / Q000235:genetics; D009479:Neuropeptides / Q000235:genetics; D010641:Phenotype; D051381:Rats; D017207:Rats, Sprague-Dawley; D012190:Retroviridae / Q000235:genetics; D064030:S100 Calcium Binding Protein G / Q000235:genetics; D012794:Sialic Acids / Q000235:genetics; D005680:gamma-Aminobutyric Acid / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*
chemical_list: D015415:Biomarkers; D064026:Calbindins; C000714848:Dcx protein, rat; D000089622:Doublecortin Domain Proteins; D000089662:Doublecortin Protein; D008869:Microtubule-Associated Proteins; D039842:Neural Cell Adhesion Molecule L1; D009479:Neuropeptides; D064030:S100 Calcium Binding Protein G; D012794:Sialic Acids; C103469:polysialyl neural cell adhesion molecule; D049452:Green Fluorescent Proteins; D005680:gamma-Aminobutyric Acid