1. Neuroscience
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Dendritic spikes in hippocampal granule cells are necessary for long-term potentiation at the perforant path synapse

  1. Sooyun Kim  Is a corresponding author
  2. Yoonsub Kim
  3. Suk-Ho Lee
  4. Won-Kyung Ho  Is a corresponding author
  1. Seoul National University College of Medicine, Korea (South), Republic of
Research Article
  • Cited 3
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Cite this article as: eLife 2018;7:e35269 doi: 10.7554/eLife.35269

Abstract

Long-term potentiation (LTP) of synaptic responses is essential for hippocampal memory function. Perforant-path (PP) synapses on hippocampal granule cells (GCs) contribute to the formation of associative memories, which are considered the cellular correlates of memory engrams. However, the mechanisms of LTP at these synapses are not well understood. Due to sparse firing activity and the voltage attenuation in their dendrites, it remains unclear how associative LTP at distal synapses occurs. Here we show that NMDA receptor-dependent LTP can be induced at PP-GC synapses without backpropagating action potentials (bAPs) in acute rat brain slices. Dendritic recordings reveal substantial attenuation of bAPs as well as local dendritic Na+ spike generation during PP-GC input. Inhibition of dendritic Na+ spikes impairs LTP induction at PP-GC synapse. These data suggest that dendritic spikes may constitute a key cellular mechanism for memory formation in the dentate gyrus.

Article and author information

Author details

  1. Sooyun Kim

    Department of Physiology, Seoul National University College of Medicine, Seoul, Korea (South), Republic of
    For correspondence
    sooyun.kim@snu.ac.kr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2035-3247
  2. Yoonsub Kim

    Department of Physiology, Seoul National University College of Medicine, Seoul, Korea (South), Republic of
    Competing interests
    The authors declare that no competing interests exist.
  3. Suk-Ho Lee

    Department of Physiology, Seoul National University College of Medicine, Seoul, Korea (South), Republic of
    Competing interests
    The authors declare that no competing interests exist.
  4. Won-Kyung Ho

    Department of Physiology, Seoul National University College of Medicine, Seoul, Korea (South), Republic of
    For correspondence
    wonkyung@snu.ac.kr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1568-1710

Funding

National Research Foundation of Korea (NRF-619 2015R1C1A1A02037776)

  • Sooyun Kim

Ministry of Education (Brain Korea 21 PLUS Program)

  • Sooyun Kim

National Research Foundation of Korea (NRF-2010-0027941)

  • Won-Kyung Ho

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the Seoul National University. All of the animals were handled according to approved institutional animal care and use committee (IACUC) of the Seoul National University. The protocol (Approval #: SNU-090115-7) was approved by the Committee on the Ethics of Animal Experiments of the Seoul National University. Animals were anesthetized by inhalation of 5% isoflurane before sacrifice, and every effort was made to minimize suffering.

Reviewing Editor

  1. John Huguenard, Stanford University School of Medicine, United States

Publication history

  1. Received: January 21, 2018
  2. Accepted: March 25, 2018
  3. Accepted Manuscript published: March 26, 2018 (version 1)
  4. Version of Record published: April 9, 2018 (version 2)

Copyright

© 2018, Kim et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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