| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Biophysical Journal 66: 1039-1050 (1994)
© 1994 the Biophysical Society
Department of Pharmacology, State University of New York Health Science Center, Brooklyn 11203.
ABSTRACT
GABAA receptor function was studied in outside-out patches from guinea pig hippocampal neurons using a drug application system with an exchange time of under 1.5 ms. Application of GABA to these patches induced a Cl- conductance that desensitized with prolonged exposure. Increasing GABA concentrations induced larger conductance increases that were associated with more complex patterns of desensitization. Smaller GABA responses desensitized with monophasic kinetics, whereas large responses displayed bi- and triphasic kinetics. Desensitization of the response to 1 mM GABA was triphasic in about 70% of the patches (tau = 15.4, 207, and 1370 ms) and biphasic in about 30% of the patches (tau = 44 and 725 ms). All phases of desensitization reversed at the Cl- equilibrium potential. Over the concentration range from 3 microM to 3 mM, both the rate and the extent of desensitization increased; however, complete desensitization was rarely observed. The increase in desensitization rate was due to an increase in the relative contribution of the faster phases with increasing GABA. The time constants of the three phases were independent of concentration. The different phases are not mediated by separate receptor populations, because double pulse experiments demonstrated interconversion among the fastest phase and the two slower phases. We demonstrate the plausibility of a model in which multiphasic desensitization is a consequence of the faster association rate at higher GABA concentrations.
This article has been cited by other articles:
![]() |
M. T. Bianchi, E. J. Botzolakis, K. F. Haas, J. L. Fisher, and R. L. Macdonald Microscopic kinetic determinants of macroscopic currents: insights from coupling and uncoupling of GABAA receptor desensitization and deactivation J. Physiol., November 1, 2007; 584(3): 769 - 787. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. I. Wilson and G. Laurent Role of GABAergic Inhibition in Shaping Odor-Evoked Spatiotemporal Patterns in the Drosophila Antennal Lobe J. Neurosci., October 5, 2005; 25(40): 9069 - 9079. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Jabs, T. Pivneva, K. Huttmann, A. Wyczynski, C. Nolte, H. Kettenmann, and C. Steinhauser Synaptic transmission onto hippocampal glial cells with hGFAP promoter activity J. Cell Sci., August 15, 2005; 118(16): 3791 - 3803. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. S Smith and Q. H. Gong Neurosteroid administration and withdrawal alter GABAA receptor kinetics in CA1 hippocampus of female rats J. Physiol., April 15, 2005; 564(2): 421 - 436. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. M. Petrini, I. Marchionni, P. Zacchi, W. Sieghart, and E. Cherubini Clustering of Extrasynaptic GABAA Receptors Modulates Tonic Inhibition in Cultured Hippocampal Neurons J. Biol. Chem., October 29, 2004; 279(44): 45833 - 45843. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. A. Wagner, C. Czajkowski, and M. V. Jones An Arginine Involved in GABA Binding and Unbinding But Not Gating of the GABAA Receptor J. Neurosci., March 17, 2004; 24(11): 2733 - 2741. [Abstract] [Full Text] [PDF] |
||||
![]() |
X.-Q. Hu, L. Zhang, R. R. Stewart, and F. F. Weight Arginine 222 in the Pre-transmembrane Domain 1 of 5-HT3A Receptors Links Agonist Binding to Channel Gating J. Biol. Chem., November 21, 2003; 278(47): 46583 - 46589. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. W. Mozrzymas, A. Barberis, K. Mercik, and E. D. Zarnowska Binding Sites, Singly Bound States, and Conformation Coupling Shape GABA-Evoked Currents J Neurophysiol, February 1, 2003; 89(2): 871 - 883. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Scheller and S. A. Forman Coupled and Uncoupled Gating and Desensitization Effects by Pore Domain Mutations in GABAA Receptors J. Neurosci., October 1, 2002; 22(19): 8411 - 8421. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. H. Ye, L. Tao, L. Zhu, and J. J. McArdle Ethanol Inhibition of Glycine-Activated Responses in Neurons of Ventral Tegmental Area of Neonatal Rats J Neurophysiol, November 1, 2001; 86(5): 2426 - 2434. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. M. Burkat, J. Yang, and K. J. Gingrich Dominant Gating Governing Transient GABAA Receptor Activity: A First Latency and Po/o Analysis J. Neurosci., September 15, 2001; 21(18): 7026 - 7036. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. R. Mellor and A. D. Randall Synaptically Released Neurotransmitter Fails to Desensitize Postsynaptic GABAA Receptors in Cerebellar Cultures J Neurophysiol, May 1, 2001; 85(5): 1847 - 1857. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. T. Bianchi, K. F. Haas, and R. L. Macdonald Structural Determinants of Fast Desensitization and Desensitization-Deactivation Coupling in GABAA Receptors J. Neurosci., February 15, 2001; 21(4): 1127 - 1136. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. H. Ye, L. Tao, J. Ren, R. Schaefer, P. L. Liu, D. A. Schiller, and J. J. McArdle Ethanol Potentiation of Glycine-Induced Responses in Dissociated Neurons of Rat Ventral Tegmental Area J. Pharmacol. Exp. Ther., January 1, 2001; 296(1): 77 - 83. [Abstract] [Full Text] |
||||
![]() |
L. S. Overstreet, M. V. Jones, and G. L. Westbrook Slow Desensitization Regulates the Availability of Synaptic GABAA Receptors J. Neurosci., November 1, 2000; 20(21): 7914 - 7921. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Feigenspan, S. Gustincich, and E. Raviola Pharmacology of GABAA Receptors of Retinal Dopaminergic Neurons J Neurophysiol, October 1, 2000; 84(4): 1697 - 1707. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. Shen, S. Mennerick, D. F. Covey, and C. F. Zorumski Pregnenolone Sulfate Modulates Inhibitory Synaptic Transmission by Enhancing GABAA Receptor Desensitization J. Neurosci., May 15, 2000; 20(10): 3571 - 3579. [Abstract] [Full Text] [PDF] |
||||
![]() |
X. Li and R. A. Pearce Effects of Halothane on GABAA Receptor Kinetics: Evidence for Slowed Agonist Unbinding J. Neurosci., February 1, 2000; 20(3): 899 - 907. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Bai, P. S. Pennefather, J. F. MacDonald, and B. A. Orser The General Anesthetic Propofol Slows Deactivation and Desensitization of GABAA Receptors J. Neurosci., December 15, 1999; 19(24): 10635 - 10646. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Kapur, K. F. Haas, and R. L. Macdonald Physiological Properties of GABAA Receptors From Acutely Dissociated Rat Dentate Granule Cells J Neurophysiol, May 1, 1999; 81(5): 2464 - 2471. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. I. Tietz, J. Kapur, and R. L. Macdonald Functional GABAA Receptor Heterogeneity of Acutely Dissociated Hippocampal CA1 Pyramidal Cells J Neurophysiol, April 1, 1999; 81(4): 1575 - 1586. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. V. Jones, Y. Sahara, J. A. Dzubay, and G. L. Westbrook Defining Affinity with the GABAA Receptor J. Neurosci., November 1, 1998; 18(21): 8590 - 8604. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. P. Harty and P. B. Manis Kinetic Analysis of Glycine Receptor Currents in Ventral Cochlear Nucleus J Neurophysiol, April 1, 1998; 79(4): 1891 - 1901. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Berger, C. Schwarz, U. Kraushaar, and H. Monyer Dentate Gyrus Basket Cell GABAA Receptors Are Blocked by Zn2+ via Changes of Their Desensitization Kinetics: An In Situ Patch-Clamp and Single-Cell PCR Study J. Neurosci., April 1, 1998; 18(7): 2437 - 2448. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. W. Mozrzymas and E. Cherubini Changes in Intracellular Calcium Concentration Affect Desensitization of GABAA Receptors in Acutely Dissociated P2-P6 Rat Hippocampal Neurons J Neurophysiol, March 1, 1998; 79(3): 1321 - 1328. [Abstract] [Full Text] [PDF] |
||||
![]() |
Q. X. Chen, K. L. Perkins, and R. K. S. Wong Zn2+ Blocks the NMDA- and Ca2+-Triggered Postexposure Current Ipe in Hippocampal Pyramidal Cells J Neurophysiol, February 1, 1998; 79(2): 1124 - 1126. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. D. Miranda and E. M. Barnes Jr. Repression of gamma -Aminobutyric Acid Type A Receptor alpha 1 Polypeptide Biosynthesis Requires Chronic Agonist Exposure J. Biol. Chem., June 27, 1997; 272(26): 16288 - 16294. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. J. Zhu and S. Vicini Neurosteroid Prolongs GABAA Channel Deactivation by Altering Kinetics of Desensitized States J. Neurosci., June 1, 1997; 17(11): 4022 - 4031. [Abstract] [Full Text] [PDF] |
||||
![]() |
Q. X. Chen, K. L. Perkins, D. W. Choi, and R. K. S. Wong Secondary Activation of a Cation Conductance Is Responsible for NMDA Toxicity in Acutely Isolated Hippocampal Neurons J. Neurosci., June 1, 1997; 17(11): 4032 - 4036. [Abstract] [Full Text] [PDF] |
||||
![]() |
Q.-Y. Liu, A. E. Schaffner, Y.-X. Li, V. Dunlap, and J. L. Barker Upregulation of GABAA Current by Astrocytes in Cultured Embryonic Rat Hippocampal Neurons J. Neurosci., May 1, 1996; 16(9): 2912 - 2923. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |