title: Heterogeneity in expression of functional ionotropic glutamate and GABA receptors in astrocytes across brain regions: insights from the thalamus.
abstract: Astrocytes may express ionotropic glutamate and gamma-aminobutyric acid (GABA) receptors, which allow them to sense and to respond to neuronal activity. However, so far the properties of astrocytes have been studied only in a few brain regions. Here, we provide the first detailed receptor analysis of astrocytes in the murine ventrobasal thalamus and compare the properties with those in other regions. To improve voltage-clamp control and avoid indirect effects during drug applications, freshly isolated astrocytes were employed. Two sub-populations of astrocytes were found, expressing or lacking α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors. AMPA receptor-bearing astrocytes displayed a lower Kir current density than cells lacking the receptors. In contrast, all cells expressed GABAA receptors. Single-cell RT-PCR was employed to identify the receptor subunits in thalamic astrocytes. Our findings add to the emerging evidence of functional heterogeneity of astrocytes, the impact of which still remains to be defined.
authors.affiliation: Institute of Cellular Neurosciences, University of Bonn, Sigmund-Freud-Strasse 25, 53105 Bonn, Germany.
authors.forename: Simon
authors.initials: S
authors.lastname: Höft
authors.affiliation: Institute of Cellular Neurosciences, University of Bonn, Sigmund-Freud-Strasse 25, 53105 Bonn, Germany.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Griemsmann
authors.affiliation: Institute of Cellular Neurosciences, University of Bonn, Sigmund-Freud-Strasse 25, 53105 Bonn, Germany.
authors.forename: Gerald
authors.initials: G
authors.lastname: Seifert
authors.affiliation: Institute of Cellular Neurosciences, University of Bonn, Sigmund-Freud-Strasse 25, 53105 Bonn, Germany christian.steinhaeuser@ukb.uni-bonn.de.
authors.forename: Christian
authors.initials: C
authors.lastname: Steinhäuser
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000378:metabolism*; D051379:Mice; D018408:Patch-Clamp Techniques / Q000379:methods; D018091:Receptors, AMPA / Q000378:metabolism; D018079:Receptors, GABA / Q000378:metabolism*; D058468:Receptors, Ionotropic Glutamate / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D059010:Single-Cell Analysis; D013788:Thalamus / Q000166:cytology* / Q000378:metabolism
chemical_list: D018091:Receptors, AMPA; D018079:Receptors, GABA; D058468:Receptors, Ionotropic Glutamate
keywords: AMPA receptors; GABAA receptors; NMDA receptors; astrocytes; heterogeneity; thalamus