title: Polarized distribution of AMPA, but not GABAA , receptors in radial glia-like cells of the adult dentate gyrus.
abstract: Glial fibrillary acidic protein (GFAP)-positive astrocytes with radial processes [radial glia (RG)-like cells] in the postnatal dentate gyrus share many of the characteristics of embryonic radial glia and appear to act as precursor cells for adult dentate neurogenesis, a process important for pattern separation and hippocampus-dependent learning. Although much work has delineated the mechanisms underlying activity-neurogenesis coupling via gamma-amino butyric acid (GABA)ergic neurotransmission on GFAP-negative transient-amplifying cells and neuroblasts, little is known regarding the effects of neurotransmitters on RG-like cells. Conflicting evidence exists for both GABA and glutamate receptors on these cells. Here, using GFAP reporter mice, we show that the somatic membrane of RG-like cells carries GABAA receptors and glutamate transporters but not ionotropic glutamate receptors, whereas 2-amino-3-(hydroxyl-5-methylisoxazole-4-yl) propionic acid (AMPA) and GABAA receptors are expressed on the processes of these cells. Almost all RG-like cells expressed the GluA2 subunit, which restricts the Ca(2+) permeability of AMPA receptors. The glial GABAA receptors mainly comprised α2/α4, β1, and γ1/γ3. The selective presence of AMPA receptors on the radial processes may be important for sensing and responding to local activity-driven glutamate release and supports the concept that RG-like astrocytes are composed of functional and structural domains.
authors: Institute of Cellular Neurosciences, University of Bonn, Bonn, Germany.
authors: Roland
authors: R
authors: Renzel
authors: Ahmed-Ramadan
authors: AR
authors: Sadek
authors: Cin-He
authors: CH
authors: Chang
authors: William P
authors: WP
authors: Gray
authors: Gerald
authors: G
authors: Seifert
authors: Christian
authors: C
authors: Steinhäuser
mesh_terms: D018750:6-Cyano-7-nitroquinoxaline-2,3-dione / Q000494:pharmacology; D027322:Amino Acid Transport System X-AG / Q000378:metabolism; D000818:Animals; D001640:Bicuculline / Q000494:pharmacology; D055592:Biophysical Phenomena / Q000187:drug effects / Q000235:genetics; D018891:Dentate Gyrus / Q000166:cytology*; D018683:Excitatory Amino Acid Agents / Q000494:pharmacology; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins / Q000235:genetics / Q000378:metabolism; D018682:GABA Agents / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects / Q000235:genetics; D005904:Glial Fibrillary Acidic Protein / Q000235:genetics / Q000378:metabolism; D018698:Glutamic Acid / Q000494:pharmacology; D049452:Green Fluorescent Proteins / Q000235:genetics; D006801:Humans; D066298:In Vitro Techniques; D008564:Membrane Potentials / Q000235:genetics / Q000502:physiology; D051379:Mice; D008822:Mice, Transgenic; D009118:Muscimol / Q000494:pharmacology; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism; D009457:Neuroglia / Q000502:physiology*; D026902:Potassium Channel Blockers / Q000494:pharmacology; D018091:Receptors, AMPA / Q000378:metabolism*; D011963:Receptors, GABA-A / Q000378:metabolism*; D019789:Tetraethylammonium / Q000494:pharmacology
chemical_list: D027322:Amino Acid Transport System X-AG; D018683:Excitatory Amino Acid Agents; C086936:Fabp7 protein, mouse; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D018682:GABA Agents; D005904:Glial Fibrillary Acidic Protein; D009419:Nerve Tissue Proteins; D026902:Potassium Channel Blockers; D018091:Receptors, AMPA; D011963:Receptors, GABA-A; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins; D009118:Muscimol; D018698:Glutamic Acid; D019789:Tetraethylammonium; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; D001640:Bicuculline