Home LiteratureArticle Details

PMID: 8265593 Published · ppublish English Journal Article Research Support, U.S. Gov't, Non-P.H.S. Research Support, U.S. Gov't, P.H.S.

Synaptic inhibition regulates associative interactions between afferents during the induction of long-term potentiation and depression.

Proceedings of the National Academy of Sciences of the United States of America ·Vol. 90 ·No. 24 ·1993-12-15 ·Pages 11578-82

Tomasulo RA, Ramirez JJ, Steward O

Abstract

The induction of long-term potentiation and depression depends upon associative interactions between synapses that converge on individual dendrites. The distance over which these associative interactions occur is limited. The present study evaluates whether this limitation is regulated by synaptic inhibition. We evaluated the associative interactions between two inputs that terminate on different proximo-distal locations along the dendrites of dentate granule cells in the presence of the gamma-aminobutyric acid (GABA) antagonist bicuculline methiodide. Local blockade of GABAergic inhibition enhanced associative interactions between nonoverlapping inputs, compared to within-animal control sites, where inhibitory transmission was intact. The results suggest that synaptic inhibition limits interactions between excitatory synapses by creating current shunts that limit the spread of depolarization within the dendritic tree.

MeSH Terms

Afferent Pathways/physiology Animals Bicuculline/pharmacology Dendrites/physiology Electric Stimulation GABA Antagonists Hippocampus/cytology,physiology Long-Term Potentiation/drug effects Male Neuronal Plasticity/drug effects,physiology Rats Rats, Sprague-Dawley Synapses/drug effects,physiology gamma-Aminobutyric Acid/physiology

Chemicals

GABA Antagonists gamma-Aminobutyric Acid Bicuculline

Authors & Affiliations

3 authors, click to expand affiliations / ORCID

Tomasulo R A

Department of Neuroscience, University of Virginia School of Medicine, Charlottesville 22908.

Ramirez J J

Steward O

References (20)

20 references, click to expand

Synapses as associative memory elements in the hippocampal formation.
Brain Res. 1979 Oct 19;175(2):233-45 PMID: 487154
Bicuculline permits the induction of long-term depression by heterosynaptic, translaminar conditioning in the hippocampal dentate gyrus.
Brain Res. 1993 Jun 11;613(2):309-12 PMID: 8186982
GABAergic synaptic boutons in the granule cell layer of rat dentate gyrus.
Brain Res. 1984 Feb 20;293(2):353-9 PMID: 6320972
Facilitation of hippocampal long-lasting potentiation by GABA antagonists.
Acta Physiol Scand. 1985 Sep;125(1):159-72 PMID: 2996303
Hippocampal long-term potentiation is induced by pairing single afferent volleys with intracellularly injected depolarizing current pulses.
Acta Physiol Scand. 1986 Feb;126(2):317-9 PMID: 3705989
Evidence that associative interactions between synapses during the induction of long-term potentiation occur within local dendritic domains.
Proc Natl Acad Sci U S A. 1988 Apr;85(7):2368-72 PMID: 3353384
Stratum lacunosum-moleculare interneurons of hippocampal CA1 region. I. Intracellular response characteristics, synaptic responses, and morphology.
J Neurosci. 1988 Apr;8(4):1400-10 PMID: 3357023
Stratum lacunosum-moleculare interneurons of hippocampal CA1 region. II. Intrasomatic and intradendritic recordings of local circuit synaptic interactions.
J Neurosci. 1988 Apr;8(4):1411-24 PMID: 3357024
Ultrastructure of stratum lacunosum-moleculare interneurons of hippocampal CA1 region.
Synapse. 1988;2(4):382-94 PMID: 3187908
Long-term potentiation induced in dendrites separated from rat's CA1 pyramidal somata does not establish a late phase.
Neurosci Lett. 1989 Feb 13;97(1-2):135-9 PMID: 2918996
Effects of uniform and non-uniform synaptic 'activation-distributions' on the cable properties of modeled cortical pyramidal neurons.
Brain Res. 1989 Dec 25;505(1):12-22 PMID: 2611664
Blockade of inhibition in a pathway with dual excitatory and inhibitory action unmasks a capability for LTP that is otherwise not expressed.
Brain Res. 1990 May 21;516(2):292-300 PMID: 2364294
Spatial overlap between populations of synapses determines the extent of their associative interaction during the induction of long-term potentiation and depression.
J Neurophysiol. 1990 Oct;64(4):1186-98 PMID: 2258741
Heterosynaptic long-term depression is facilitated by blockade of inhibition in area CA1 of the hippocampus.
Brain Res. 1991 Apr 19;546(2):336-40 PMID: 1829976
NMDA-dependent heterosynaptic long-term depression in the dentate gyrus of anaesthetized rats.
Synapse. 1992 Jan;10(1):1-6 PMID: 1531559
LTP-associated EPSP/spike dissociation in the dentate gyrus: GABAergic and non-GABAergic components.
Brain Res. 1991 Oct 4;561(1):27-34 PMID: 1797347
Inhibitory contacts on dendritic spines of the dentate fascia.
Brain Res. 1992 Apr 17;577(2):331-6 PMID: 1606504
Electrophysiological and pharmacological characterization of perforant path synapses in CA1: mediation by glutamate receptors.
J Neurophysiol. 1992 Jul;68(1):1-8 PMID: 1355524
Shunting of excitatory input to dentate gyrus granule cells by a depolarizing GABAA receptor-mediated postsynaptic conductance.
J Neurophysiol. 1992 Jul;68(1):197-212 PMID: 1381418
Five types of basket cell in the hippocampal dentate gyrus: a combined Golgi and electron microscopic study.
J Neurocytol. 1983 Aug;12(4):577-97 PMID: 6619905

Article Info

Journal

Proceedings of the National Academy of Sciences of the United States of America

Abbr.

Proc Natl Acad Sci U S A

ISSN

0027-8424

DOI

10.1073/pnas.90.24.11578

Published

1993-12-15

Pages

11578-82

Language

English

Region

United States

NLM ID

7505876

PMCID

PMC48027

Subset

Grants

NINDS NIH HHS · NS01438 · United States

External Links

PubMed source DOI: 10.1073/pnas.90.24.11578 PMC Full Text View journal details

Analysis Services

Synaptic inhibition regulates associative interactions between afferents during the induction of long-term potentiation and depression.

Contact

WeChat Official Account