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

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

This Article Full Text Full Text (PDF) 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 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 Web of Science (34) Citing Articles via Google Scholar Google Scholar Articles by van Haeften, T. Articles by P. Witter, M. Search for Related Content PubMed PubMed Citation Articles by van Haeften, T. Articles by P. Witter, M.

 Previous Article

Volume 17, Number 2, Issue of January 15, 1997 pp. 862-874
Copyright ©1997 Society for Neuroscience

GABAergic Presubicular Projections to the Medial Entorhinal Cortex of the Rat

Received Aug. 6, 1996; revised Oct. 31, 1996; accepted Nov. 5, 1996.

Theo van Haeften, Floris G. Wouterlood, Barbara Jorritsma-Byham, and Menno P. Witter

Graduate School for Neurosciences Amsterdam, Research Institute Neurosciences Vrije Universiteit, Department of Anatomy and Embryology, Amsterdam, The Netherlands

We characterized presubicular neurons giving rise to bilateral projections to the medial entorhinal cortex (MEA) of the rat. Retrograde labeling of presubiculo-entorhinal projections with horseradish peroxidase and subsequent GABA immunocytochemistry revealed that 20-30% of the ipsilaterally projecting neurons are GABAergic. No GABAergic projections to the contralateral MEA were observed. GABAergic projection neurons were observed only in the dorsal part of the presubiculum, which, when taking into account the topography of presubicular projections to MEA, indicates that only the dorsal part of MEA receives GABAergic input. The GABAergic projection neurons constitute ~30-40% of all GABAergic neurons present in the superficial layers of the dorsal presubiculum. Using double-label fluorescent retrograde tracing, we found that the ipsilateral and contralateral presubiculo-entorhinal projections originate from different populations of neurons. Anterograde labeling of presubiculo-entorhinal projections and electron microscopical analysis of labeled terminals substantiated the presence of a restricted GABAergic presubiculo-entorhinal projection. A small fraction of afferents to only ipsilateral dorsal MEA formed symmetrical synapses with dendritic shafts. No symmetrical synapses on spines were noted. Most afferents to the dorsal part of ipsilateral MEA, as well as all afferents to the remaining ipsilateral and contralateral MEA, formed asymmetrical synapses with both spines and dendritic shafts in an almost equal ratio. Thus, we conclude that the majority of the presubiculo-entorhinal projections exert an excitatory effect on both principal neurons and interneurons. The projections from the dorsal part of the presubiculum comprise a small inhibitory component that originates from GABAergic neurons and targets entorhinal interneurons.

Key words: presubiculum; GABA; projection neurons; retrograde tracing; double-fluorescence tracing; electron microscopy; feedforward disinhibition

This article has been cited by other articles:

				S. Jinno, T. Klausberger, L. F. Marton, Y. Dalezios, J. D. B. Roberts, P. Fuentealba, E. A. Bushong, D. Henze, G. Buzsaki, and P. Somogyi Neuronal Diversity in GABAergic Long-Range Projections from the Hippocampus J. Neurosci., August 15, 2007; 27(33): 8790 - 8804. [Abstract] [Full Text] [PDF]

				J. Apergis-Schoute, A. Pinto, and D. Pare Muscarinic Control of Long-Range GABAergic Inhibition within the Rhinal Cortices J. Neurosci., April 11, 2007; 27(15): 4061 - 4071. [Abstract] [Full Text] [PDF]

				E. Labyt, L. Uva, M. de Curtis, and F. Wendling Realistic Modeling of Entorhinal Cortex Field Potentials and Interpretation of Epileptic Activity in the Guinea Pig Isolated Brain Preparation J Neurophysiol, July 1, 2006; 96(1): 363 - 377. [Abstract] [Full Text] [PDF]

				F. Sargolini, M. Fyhn, T. Hafting, B. L. McNaughton, M. P. Witter, M.-B. Moser, and E. I. Moser Conjunctive representation of position, direction, and velocity in entorhinal cortex. Science, May 5, 2006; 312(5774): 758 - 762. [Abstract] [Full Text] [PDF]

				E. A. Tolner, F. Kloosterman, E. A. van Vliet, M. P. Witter, F. H. L. da Silva, and J. A. Gorter Presubiculum Stimulation In Vivo Evokes Distinct Oscillations in Superficial and Deep Entorhinal Cortex Layers in Chronic Epileptic Rats J. Neurosci., September 21, 2005; 25(38): 8755 - 8765. [Abstract] [Full Text] [PDF]

				M. Fyhn, S. Molden, M. P. Witter, E. I. Moser, and M.-B. Moser Spatial Representation in the Entorhinal Cortex Science, August 27, 2004; 305(5688): 1258 - 1264. [Abstract] [Full Text] [PDF]

				H. E. Scharfman, J. H. Goodman, F. Du, and R. Schwarcz Chronic Changes in Synaptic Responses of Entorhinal and Hippocampal Neurons After Amino-Oxyacetic Acid (AOAA)-Induced Entorhinal Cortical Neuron Loss J Neurophysiol, December 1, 1998; 80(6): 3031 - 3046. [Abstract] [Full Text] [PDF]

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help