1. Neuroscience
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Dendritic osmosensors modulate activity-induced calcium influx in oxytocinergic magnocellular neurons of the mouse PVN

  1. Wanhui Sheng  Is a corresponding author
  2. Scott W Harden  Is a corresponding author
  3. Yalun Tan  Is a corresponding author
  4. Eric G Krause  Is a corresponding author
  5. Charles J Frazier  Is a corresponding author
  1. University of Florida, United States
Research Article
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Cite this article as: eLife 2021;10:e63486 doi: 10.7554/eLife.63486

Abstract

Hypothalamic oxytocinergic magnocellular neurons have a fascinating ability to release peptide from both their axon terminals and from their dendrites. Existing data indicates that the relationship between somatic activity and dendritic release is not constant, but the mechanisms through which this relationship can be modulated are not completely understood. Here we use a combination of electrical and optical recording techniques to quantify activity-induced calcium influx in proximal vs. distal dendrites of oxytocinergic magnocellular neurons located in the paraventricular nucleus of the hypothalamus (OT-MCNs). Results reveal that the dendrites of OT-MCNs are weak conductors of somatic voltage changes, however activity-induced dendritic calcium influx can be robustly regulated by both osmosensitive and non-osmosensitive ion channels located along the dendritic membrane. Overall, this study reveals that dendritic conductivity is a dynamic and endogenously regulated feature of OT-MCNs that is likely to have substantial functional impact on central oxytocin release.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for all figures.

Article and author information

Author details

  1. Wanhui Sheng

    Department of Pharmacodynamics, University of Florida, Gainesville, United States
    For correspondence
    shengwanhui@ufl.edu
    Competing interests
    The authors declare that no competing interests exist.
  2. Scott W Harden

    Department of Pharmacodynamics, University of Florida, Gainesville, United States
    For correspondence
    swharden@ufl.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0757-1979
  3. Yalun Tan

    Department of Pharmacodynamics, University of Florida, Gainesville, United States
    For correspondence
    yaluntan@stanford.edu
    Competing interests
    The authors declare that no competing interests exist.
  4. Eric G Krause

    Department of Pharmacodynamics, University of Florida, Gainesville, United States
    For correspondence
    EKrause@cop.ufl.edu
    Competing interests
    The authors declare that no competing interests exist.
  5. Charles J Frazier

    Department of Pharmacodynamics, University of Florida, Gainesville, United States
    For correspondence
    cjfraz@ufl.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3550-4789

Funding

National Institute of Mental Health (R01MH104641)

  • Charles J Frazier

National Heart, Lung, and Blood Institute (R01HL122494)

  • Eric G Krause

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 National Institutes of Health. All animal procedures were reviewed and approved by the Institutional Animal Care and Use Committee (IACUC) at the University of Florida (under protocol # 201701866).

Reviewing Editor

  1. Ryohei Yasuda, Max Planck Florida Institute for Neuroscience, United States

Publication history

  1. Received: September 25, 2020
  2. Preprint posted: January 26, 2021 (view preprint)
  3. Accepted: July 11, 2021
  4. Accepted Manuscript published: July 12, 2021 (version 1)
  5. Version of Record published: September 22, 2021 (version 2)

Copyright

© 2021, Sheng 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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