QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

The Journal of Neuroscience, June 17, 2009, 29(24):7776-7787; doi:10.1523/JNEUROSCI.1527-09.2009

This Article Full Text Full Text (PDF) Supplemental Data Submit an eLetter Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map 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 Web of Science (2) Citing Articles via Google Scholar Google Scholar Articles by Dehorter, N. Articles by Hammond, C. Search for Related Content PubMed PubMed Citation Articles by Dehorter, N. Articles by Hammond, C.

 Previous Article  |  Next Article 

Cellular/Molecular
Dopamine-Deprived Striatal GABAergic Interneurons Burst and Generate Repetitive Gigantic IPSCs in Medium Spiny Neurons

Nathalie Dehorter,¹ Celine Guigoni,² Catherine Lopez,¹ June Hirsch,¹ Alexandre Eusebio,¹ Yehezkel Ben-Ari,¹ and Constance Hammond¹

¹Institut de Neurobiologie de la Méditerranée Unité Mixte de Recherche (UMR) 901, Inserm and Aix Marseille II University, 13009 Marseille, France, and ²Centre National de la Recherche Scientifique UMR 5227, Université Bordeaux 2, 33076 Bordeaux, France

Correspondence should be addressed to Constance Hammond, Institut de Neurobiologie de la Méditerranée Unité 901, Inserm, 163 route de Luminy, BP 13, 13273 Marseille Cedex 9, France. Email: hammond{at}inmed.univ-mrs.fr

Striatal GABAergic microcircuits modulate cortical responses and movement execution in part by controlling the activity of medium spiny neurons (MSNs). How this is altered by chronic dopamine depletion, such as in Parkinson's disease, is not presently understood. We now report that, in dopamine-depleted slices of the striatum, MSNs generate giant spontaneous postsynaptic GABAergic currents (single or in bursts at 60 Hz) interspersed with silent episodes, rather than the continuous, low-frequency GABAergic drive (5 Hz) observed in control MSNs. This shift was observed in one-half of the MSN population, including both "D₁-negative" and "D₁-positive" MSNs. Single GABA and NMDA channel recordings revealed that the resting membrane potential and reversal potential of GABA were similar in control and dopamine-depleted MSNs, and depolarizing, but not excitatory, actions of GABA were observed. Glutamatergic and cholinergic antagonists did not block the GABAergic oscillations, suggesting that they were generated by GABAergic neurons. In support of this, cell-attached recordings revealed that a subpopulation of intrastriatal GABAergic interneurons generated bursts of spikes in dopamine-deprived conditions. This subpopulation included low-threshold spike interneurons but not fast-spiking interneurons, cholinergic interneurons, or MSNs. Therefore, a population of local GABAergic interneurons shifts from tonic to oscillatory mode when dopamine deprived and gives rise to spontaneous repetitive giant GABAergic currents in one-half the MSNs. We suggest that this may in turn alter integration of cortical signals by MSNs.

---

Received March 31, 2009; revised May 6, 2009; accepted May 6, 2009.

Correspondence should be addressed to Constance Hammond, Institut de Neurobiologie de la Méditerranée Unité 901, Inserm, 163 route de Luminy, BP 13, 13273 Marseille Cedex 9, France. Email: hammond{at}inmed.univ-mrs.fr

This article has been cited by other articles:

				J. G. Partridge, M. J. Janssen, D. Y. T. Chou, K. Abe, Z. Zukowska, and S. Vicini Excitatory and Inhibitory Synapses in Neuropeptide Y-Expressing Striatal Interneurons J Neurophysiol, November 1, 2009; 102(5): 3038 - 3045. [Abstract] [Full Text] [PDF]

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help