help button home button Biophys. J.
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
Biophys. J. BioFAST: First Published June 10, 2005. doi:10.1529/biophysj.105.061572
© 2005 by the Biophysical Society.

A more recent version of this article appeared on September 1, 2005.
This Article
Right arrow Full Text (Rapid PDF)
Right arrow All Versions of this Article:
biophysj.105.061572v1
89/3/1657    most recent
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Aubrey, K. R.
Right arrow Articles by Clements, J. D.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Aubrey, K. R.
Right arrow Articles by Clements, J. D.

CHANNELS, RECEPTORS, AND ELECTRICAL SIGNALING

DYNAMICS OF FORWARD AND REVERSE TRANSPORT BY THE GLIAL GLYCINE TRANSPORTER, GLYT1B

Karin R. Aubrey 1*, Robert J. Vandenberg 2 and John D. Clements 3

1 University of Sydney; Ecole Normale Supérieure
2 University of Sydney
3 Australian National University

* To whom correspondence should be addressed. E-mail: aubrey{at}biologie.ens.fr.

Submitted on February 18, 2005
Revised on April 25, 2005
Accepted on 18 May 2005


  Abstract
Glycine is a co-agonist at the N-methyl-D-aspartate receptor. Changes in extracellular glycine concentration may modulate N-methyl-D-aspartate receptor function and excitatory synaptic transmission. The GLYT1 glycine transporter is present in glia surrounding excitatory synapses, and plays a key role in regulating extracellular glycine concentration. We investigated the kinetic and other biophysical properties of GLYT1b, stably expressed in CHO cells, using whole-cell patch clamp techniques. Application of glycine produced an inward current, which decayed within a few seconds to a steady-state level. When glycine was removed a transient outward current was observed, consistent with reverse transport of accumulated glycine. The outward current was enhanced by elevating intracellular or lowering extracellular [Na+], and was modulated by changes in extracellular [glycine] and time of glycine application. We developed a model of GLYT1b function, which accurately describes the time course of the transporter current under a range of experimental conditions. The model predicts that glial uptake of glycine will decay toward zero during a sustained period of elevated glycine concentration. This property of GLYT1b may permit spillover from glycinergic terminals to nearby excitatory terminals during a prolonged burst of inhibitory activity, and reverse transport may extend the period of elevated glycine concentration beyond the end of the inhibitory burst.

Key Words: CNS, amino acid transporters, glycine release, kinetic modeling, whole cell electrophysiology




This article has been cited by other articles:


Home page
 Mol. Pharmacol.Home page
M. Mezler, W. Hornberger, R. Mueller, M. S. W. Amberg, W. Braje, M. Ochse, H. Schoemaker, and B. Behl
Inhibitors of GlyT1 Affect Glycine Transport via Discrete Binding Sites
Mol. Pharmacol., December 1, 2008; 74(6): 1705 - 1715.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurosci.Home page
K. Erreger, C. Grewer, J. A. Javitch, and A. Galli
Currents in Response to Rapid Concentration Jumps of Amphetamine Uncover Novel Aspects of Human Dopamine Transporter Function
J. Neurosci., January 23, 2008; 28(4): 976 - 989.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
Copyright © 2005 by the Biophysical Society.