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) All Versions of this Article: 95/2/1285    most recent 00598.2005v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science 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 ISI Web of Science (10) Citing Articles via Google Scholar Google Scholar Articles by Bracci, E. Articles by Panzeri, S. Search for Related Content PubMed PubMed Citation Articles by Bracci, E. Articles by Panzeri, S.

REPORT

Excitatory GABAergic Effects in Striatal Projection Neurons

Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom

Submitted 9 June 2005; accepted in final form 26 October 2005

The ability of synaptically released GABA to facilitate action potential generation in striatal projection neurons was studied in brain slices using current-clamp, gramicidin-perforated whole cell recordings. Evoked GABAergic postsynaptic potentials (PSPs) were pharmacologically isolated with ionotropic glutamate receptor antagonists. Subthreshold depolarizing current injections were paired with GABAergic PSPs at different intervals. GABAergic PSPs were able to convert current injection-induced depolarizations from subthreshold to suprathreshold, but only when they preceded the current injection by an appropriate interval; accordingly, action potentials were observed 4–140 ms after the onset of the GABAergic PSP, and their likelihood was maximal after 50–60 ms. The GABAergic excitatory effects were fully blocked by the GABA_A receptor antagonist bicuculline. Appropriately timed GABA PSPs decreased the time taken by current injections to depolarize projection neurons, causing an apparent reduction in the spike threshold. In control solution, the ability of evoked PSPs (comprising both glutamatergic and GABAergic components) to reach spike threshold was often impaired by bicuculline. We conclude that GABAergic PSPs can exert excitatory effects on projection neurons and that this ability crucially depends on the timing between the GABAergic event and a concomitant depolarizing input.

This article has been cited by other articles:

				C. Blomeley and E. Bracci Substance P depolarizes striatal projection neurons and facilitates their glutamatergic inputs J. Physiol., April 15, 2008; 586(8): 2143 - 2155. [Abstract] [Full Text] [PDF]

				Z. Liu, Y. Otsu, C. Vasuta, H. Nawa, and T. H. Murphy Action-Potential-Independent GABAergic Tone Mediated by Nicotinic Stimulation of Immature Striatal Miniature Synaptic Transmission J Neurophysiol, August 1, 2007; 98(2): 581 - 593. [Abstract] [Full Text] [PDF]

				P. Pakhotin and E. Bracci Cholinergic Interneurons Control the Excitatory Input to the Striatum J. Neurosci., January 10, 2007; 27(2): 391 - 400. [Abstract] [Full Text] [PDF]

				F. Kasanetz, L. A. Riquelme, P. O'Donnell, and M. G. Murer Turning off cortical ensembles stops striatal Up states and elicits phase perturbations in cortical and striatal slow oscillations in rat in vivo J. Physiol., November 15, 2006; 577(1): 97 - 113. [Abstract] [Full Text] [PDF]