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: 96/5/2593    most recent 00555.2006v1 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 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 (6) Citing Articles via Google Scholar Google Scholar Articles by Lam, Y.-W. Articles by Sherman, S. M. Search for Related Content PubMed PubMed Citation Articles by Lam, Y.-W. Articles by Sherman, S. M.

Mapping of the Functional Interconnections Between Thalamic Reticular Neurons Using Photostimulation

Department of Neurobiology, Pharmacology and Physiology, The University of Chicago, Chicago, Illinois

Submitted 24 May 2006; accepted in final form 18 July 2006

The thalamic reticular nucleus is strategically located in the axonal pathways between thalamus and cortex, and reticular cells exert strong, topographic inhibition on thalamic relay cells. Although evidence exists that reticular neurons are interconnected through conventional and electrical synapses, the spatial extent and relative strength of these synapses are unclear. To address these issues, we used uncaging of glutamate by laser-scanning photostimulation to provide precisely localized and consistent activation of reticular cell bodies and dendrites in an in vitro slice preparation from the rat as a means to study reticulo-reticular connections. Among the 47 recorded reticular neurons, 29 (62%) received GABAergic axodendritic input from an area immediately surrounding each of the recorded cell bodies, and 8 (17%) responded with depolarizing spikelets, suggesting inputs through electrical synapses. We also found that TTX completely blocked all evoked IPSCs, implying that any dendrodendritic synapses between reticular cells either are relatively weak, have no nearby glutamatergic receptors, or are dependent on back-propagation of action potentials. Finally, we showed that the GABAergic connections between reticular cells are weaker than those from reticular cells to relay cells. Our results suggest that the GABAergic axodendritic synapse is the dominant form of reticulo-reticular connectivity, and because they are much weaker than the reticulo-relay cell synapses, their functional purpose may be to regulate the spatial extent of the reticular inhibition on relay cells.

This article has been cited by other articles:

				N. Cotillon-Williams, C. Huetz, E. Hennevin, and J.-M. Edeline Tonotopic Control of Auditory Thalamus Frequency Tuning by Reticular Thalamic Neurons J Neurophysiol, March 1, 2008; 99(3): 1137 - 1151. [Abstract] [Full Text] [PDF]

				Y.-W. Lam and S. M. Sherman Different Topography of the Reticulothalmic Inputs to First- and Higher-Order Somatosensory Thalamic Relays Revealed Using Photostimulation J Neurophysiol, November 1, 2007; 98(5): 2903 - 2909. [Abstract] [Full Text] [PDF]

				X.-B. Liu, J. Coble, G. van Luijtelaar, and E. G. Jones Reticular nucleus-specific changes in {alpha}3 subunit protein at GABA synapses in genetically epilepsy-prone rats PNAS, July 24, 2007; 104(30): 12512 - 12517. [Abstract] [Full Text] [PDF]