Dendritic sodium spikes are required for long-term potentiation at distal synapses on hippocampal pyramidal neurons

  1. Yujin Kim
  2. Ching-Lung Hsu
  3. Mark S Cembrowski
  4. Brett D Mensh
  5. Nelson Spruston  Is a corresponding author
  1. Janelia Research Campus, Howard Hughes Medical Institute, United States

Abstract

Dendritic integration of synaptic inputs mediates rapid neural computation as well as longer-lasting plasticity. Several channel types can mediate dendritically initiated spikes (dSpikes), which may impact information processing and storage across multiple timescales; however, the roles of different channels in the rapid versus long-term effects of dSpikes are unknown. We show here that dSpikes mediated by Nav channels (blocked by a low concentration of TTX) are required for long-term potentiation (LTP) in the distal apical dendrites of hippocampal pyramidal neurons. Furthermore, imaging, simulations, and buffering experiments all support a model whereby fast Nav channel-mediated dSpikes (Na-dSpikes) contribute to LTP induction by promoting large, transient, localized increases in intracellular calcium concentration near the calcium-conducting pores of NMDAR and L-type Cav channels. Thus, in addition to contributing to rapid neural processing, Na-dSpikes are likely to contribute to memory formation via their role in long-lasting synaptic plasticity.

Article and author information

Author details

  1. Yujin Kim

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Ching-Lung Hsu

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Mark S Cembrowski

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Brett D Mensh

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Nelson Spruston

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    For correspondence
    sprustonn@janelia.hhmi.org
    Competing interests
    The authors declare that no competing interests exist.

Ethics

Animal experimentation: All animal procedures were approved by the Animal Care and Use Committees 591 at the HHMI Janelia Research Campus and Northwestern University.

Reviewing Editor

  1. Gary L Westbrook, Vollum Institute, United States

Publication history

  1. Received: January 9, 2015
  2. Accepted: August 5, 2015
  3. Accepted Manuscript published: August 6, 2015 (version 1)
  4. Version of Record published: September 29, 2015 (version 2)

Copyright

© 2015, 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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  1. Yujin Kim
  2. Ching-Lung Hsu
  3. Mark S Cembrowski
  4. Brett D Mensh
  5. Nelson Spruston
(2015)
Dendritic sodium spikes are required for long-term potentiation at distal synapses on hippocampal pyramidal neurons
eLife 4:e06414.
https://doi.org/10.7554/eLife.06414
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