title: Glycine transporter 1 expression in the ventral respiratory group is restricted to protoplasmic astrocytes.
abstract: The lack of the glycine transporter 1 (GlyT1) leads to early postnatal death due to failure of respiratory network activity. Here we demonstrate a segregated expression of GlyT1 on different astroglial cell populations of the ventral respiratory group. In TgN(hGFAP-EGFP) mice a combined immunohistochemical and electrophysiological approach was used to define the cellular expression of GlyT1 in the respiratory network. EGFP-labeled cells with outwardly rectifying current-voltage relationship did not express glycine transporter 1, while GlyT1 was abundantly expressed in mature protoplasmic astrocytes, which are electrophysiologically characterized by a large potassium conductance, a more negative membrane potential and the expression of glutamate transporters. Taken together, the vital capacity for the clearance of extracellular glycine is restricted to a subpopulation of astroglial cells.
authors.affiliation: Department of Neuro- and Sensory Physiology, University of Göttingen, Germany.
authors.forename: Katalin
authors.initials: K
authors.lastname: Szoke
authors.forename: Kai
authors.initials: K
authors.lastname: Härtel
authors.forename: Dennis
authors.initials: D
authors.lastname: Grass
authors.forename: Petra G
authors.initials: PG
authors.lastname: Hirrlinger
authors.forename: Johannes
authors.initials: J
authors.lastname: Hirrlinger
authors.forename: Swen
authors.initials: S
authors.lastname: Hülsmann
mesh_terms: D027322:Amino Acid Transport System X-AG / Q000378:metabolism; D000818:Animals; D001253:Astrocytes / Q000166:cytology / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D045604:Extracellular Fluid / Q000378:metabolism; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D005998:Glycine / Q000378:metabolism*; D050487:Glycine Plasma Membrane Transport Proteins / Q000378:metabolism*; D049452:Green Fluorescent Proteins; D007150:Immunohistochemistry; D008564:Membrane Potentials / Q000502:physiology; D051379:Mice; D008822:Mice, Transgenic; D009415:Nerve Net / Q000502:physiology; D009433:Neural Inhibition / Q000502:physiology; D009924:Organ Culture Techniques; D015221:Potassium Channels / Q000378:metabolism; D012125:Respiratory Center / Q000166:cytology / Q000378:metabolism*; D009435:Synaptic Transmission / Q000502:physiology
chemical_list: D027322:Amino Acid Transport System X-AG; D015415:Biomarkers; D005904:Glial Fibrillary Acidic Protein; D050487:Glycine Plasma Membrane Transport Proteins; D015221:Potassium Channels; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins; D005998:Glycine