Single synapse evaluation of the postsynaptic NMDA receptors targeted by evoked and spontaneous neurotransmission

  1. Austin L Reese
  2. Ege T Kavalali  Is a corresponding author
  1. University of Texas Southwestern Medical Center, United States

Abstract

Recent studies indicate that within individual synapses spontaneous and evoked release processes are segregated and regulated independently. In the hippocampus, earlier electrophysiological recordings suggested that spontaneous and evoked glutamate release can activate separate groups of postsynaptic NMDA receptors with limited overlap. However, it is still unclear how this separation of NMDA receptors is distributed across individual synapses. In a previous paper (Reese and Kavalali, 2015) we showed that NMDA receptor mediated spontaneous transmission signals to the postsynaptic protein translation machinery through Ca2+-induced Ca2+ release. Here, we show that in rat hippocampal neurons although spontaneous and evoked glutamate release driven NMDA receptor mediated Ca2+ transients often occur at the same synapse, these two signals do not show significant correlation or cross talk.

Article and author information

Author details

  1. Austin L Reese

    Departments of Neuroscience, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Ege T Kavalali

    Departments of Neuroscience, University of Texas Southwestern Medical Center, Dallas, United States
    For correspondence
    ege.kavalali@utsouthwestern.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1777-227X

Funding

National Institute of Mental Health

  • Ege T Kavalali

National Institute of Neurological Disorders and Stroke

  • Austin L Reese
  • Ege T Kavalali

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

Ethics

Animal experimentation: 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 National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols of the UT Southwestern Medical Center (APN# 0866-06-05-1).

Reviewing Editor

  1. Indira M Raman, Northwestern University, United States

Publication history

  1. Received: September 1, 2016
  2. Accepted: November 23, 2016
  3. Accepted Manuscript published: November 24, 2016 (version 1)
  4. Version of Record published: December 9, 2016 (version 2)
  5. Version of Record updated: December 14, 2016 (version 3)

Copyright

© 2016, Reese & Kavalali

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. Austin L Reese
  2. Ege T Kavalali
(2016)
Single synapse evaluation of the postsynaptic NMDA receptors targeted by evoked and spontaneous neurotransmission
eLife 5:e21170.
https://doi.org/10.7554/eLife.21170

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