HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Fucile, S. Articles by Bregestovski, P. Search for Related Content PubMed PubMed Citation Articles by Fucile, S. Articles by Bregestovski, P.

Comparison of glycine and GABA actions on the zebrafish homomeric glycine receptor

Sergio Fucile, Didier de Saint Jan, Brigitte David-Watine, Henri Korn and Piotr Bregestovski

Glycine and GABA can be co-released from the same presynaptic terminals and in lower vertebrates they can activate the same glycine receptors (GlyRs). Thus we examined the effects of these two inhibitory transmitters on the homomeric GlyRs formed by the Z1 subunit, of the zebrafish using two expression systems: Xenopus oocytes and the human BOSC 23 cell line.

The apparent affinity (EC₅₀) of Z1 for these neurotransmitters was highly variable. In Xenopus oocytes the EC₅₀ ranged from 37 to 360 µM (mean ± s.d. EC₅₀ 116 ± 75 µM, n = 83) for glycine and from 8 to 120 mM (mean EC₅₀ 40 ± 30 mM, n = 37) for GABA.

In BOSC cells the EC₅₀ varied from 9 to 92 µM (mean EC₅₀ 33 ± 17 µM, n = 19) and from 0·7 to 19·1 mM (mean EC₅₀ 4·9 ± 4·7 mM, n = 29) for glycine and GABA, respectively.

GABA activated Z1 GlyRs either as a weak or full agonist: its efficacy (defined as I_max,GABA/I_max,Gly) was related to EC₅₀ by an exponential relationship. A linear relationship was observed between EC₅₀ values for GABA and glycine.

In outside-out patches, GABA and glycine activated Z1 with identical single-channel conductances (85-100 pS), but with different kinetics and marked effect of concentration on burst duration for glycine only.

In outside-out patches deactivation time constants were concentration dependent for glycine, but not for GABA.

Our data demonstrate that the kinetics of glycine and GABA interactions with Z1 are different and that they determine the properties of these neurotransmitter actions on the GlyR.

This article has been cited by other articles:

				S. Fucile, R. Miledi, and F. Eusebi Effects of cyclothiazide on GluR1/AMPA receptors PNAS, February 21, 2006; 103(8): 2943 - 2947. [Abstract] [Full Text] [PDF]

				M. Mukhtarov, D. Ragozzino, and P. Bregestovski Dual Ca2+ modulation of glycinergic synaptic currents in rodent hypoglossal motoneurones J. Physiol., December 15, 2005; 569(3): 817 - 831. [Abstract] [Full Text] [PDF]

				J. W. Lynch Molecular Structure and Function of the Glycine Receptor Chloride Channel Physiol Rev, October 1, 2004; 84(4): 1051 - 1095. [Abstract] [Full Text] [PDF]

				G. B. Awatramani, R. Turecek, and L. O. Trussell Inhibitory Control at a Synaptic Relay J. Neurosci., March 17, 2004; 24(11): 2643 - 2647. [Abstract] [Full Text] [PDF]

				Y. Li, L.-J. Wu, P. Legendre, and T.-L. Xu Asymmetric Cross-inhibition between GABAA and Glycine Receptors in Rat Spinal Dorsal Horn Neurons J. Biol. Chem., October 3, 2003; 278(40): 38637 - 38645. [Abstract] [Full Text] [PDF]

				P. Legendre, E. Muller, C. I. Badiu, J. Meier, C. Vannier, and A. Triller Desensitization of Homomeric alpha 1 Glycine Receptor Increases with Receptor Density Mol. Pharmacol., October 1, 2002; 62(4): 817 - 827. [Abstract] [Full Text] [PDF]

				G. Martin and G. R. Siggins Electrophysiological Evidence for Expression of Glycine Receptors in Freshly Isolated Neurons from Nucleus Accumbens J. Pharmacol. Exp. Ther., September 1, 2002; 302(3): 1135 - 1145. [Abstract] [Full Text] [PDF]

				M. Beato, P. J. Groot-Kormelink, D. Colquhoun, and L. G. Sivilotti Openings of the Rat Recombinant {alpha}1 Homomeric Glycine Receptor as a Function of the Number of Agonist Molecules Bound J. Gen. Physiol., April 29, 2002; 119(5): 443 - 466. [Abstract] [Full Text] [PDF]

				J. Kehoe and C. Vulfius Independence of and Interactions between GABA-, Glutamate-, and Acetylcholine-Activated Cl Conductances in Aplysia Neurons J. Neurosci., December 1, 2000; 20(23): 8585 - 8596. [Abstract] [Full Text] [PDF]

				D. W. Ali, P. Drapeau, and P. Legendre Development of Spontaneous Glycinergic Currents in the Mauthner Neuron of the Zebrafish Embryo J Neurophysiol, October 1, 2000; 84(4): 1726 - 1736. [Abstract] [Full Text] [PDF]

				S. J. Zottoli and D. S. Faber {blacksquare} Review : The Mauthner Cell: What Has it Taught us? Neuroscientist, February 1, 2000; 6(1): 26 - 38. [Abstract] [PDF]

				M. Beato, P. J. Groot-Kormelink, D. Colquhoun, and L. G. Sivilotti Openings of the Rat Recombinant {alpha}1 Homomeric Glycine Receptor as a Function of the Number of Agonist Molecules Bound J. Gen. Physiol., April 29, 2002; 119(5): 443 - 466. [Abstract] [Full Text] [PDF]