Non-linear developmental trajectory of electrical phenotype in rat substantia nigra pars compacta dopaminergic neurons

  1. Martial A Dufour
  2. Adele Woodhouse
  3. Julien Amendola
  4. Jean-Marc Goaillard  Is a corresponding author
  1. Inserm UMR 1072, Université de la Méditerranée, France
  2. University of Tasmania, Australia

Abstract

Neurons have complex electrophysiological properties, however, it is often difficult to determine which properties are the most relevant to neuronal function. By combining current-clamp measurements of electrophysiological properties with multi-variate analysis (hierarchical clustering, principal component analysis), we were able to characterize the postnatal development of substantia nigra dopaminergic neurons' electrical phenotype in an unbiased manner, such that subtle changes in phenotype could be analyzed. We show that the intrinsic electrical phenotype of these neurons follows a non-linear trajectory reaching maturity by postnatal day 14, with two developmental transitions occurring between postnatal days 3-5 and 9-11. This approach also predicted which parameters play a critical role in phenotypic variation, enabling us to determine (using pharmacology, dynamic-clamp) that changes in the leak, sodium and calcium-activated potassium currents are central to these two developmental transitions. This analysis enables an unbiased definition of neuronal type/phenotype that is applicable to a range of research questions.

Article and author information

Author details

  1. Martial A Dufour

    Inserm UMR 1072, Université de la Méditerranée, Marseille, France
    Competing interests
    The authors declare that no competing interests exist.
  2. Adele Woodhouse

    University of Tasmania, Hobart, Australia
    Competing interests
    The authors declare that no competing interests exist.
  3. Julien Amendola

    Inserm UMR 1072, Université de la Méditerranée, Marseille, France
    Competing interests
    The authors declare that no competing interests exist.
  4. Jean-Marc Goaillard

    Inserm UMR 1072, Université de la Méditerranée, Marseille, France
    For correspondence
    jean-marc.goaillard@univ-amu.fr
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Ronald L Calabrese, Emory University, United States

Ethics

Animal experimentation: All experiments were performed according to the European and institutional guidelines for the care and use of laboratory animals (Council Directive 86/609/EEC and French National Research Council).

Version history

  1. Received: July 17, 2014
  2. Accepted: October 19, 2014
  3. Accepted Manuscript published: October 20, 2014 (version 1)
  4. Accepted Manuscript updated: October 23, 2014 (version 2)
  5. Version of Record published: November 25, 2014 (version 3)

Copyright

© 2014, Dufour 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. Martial A Dufour
  2. Adele Woodhouse
  3. Julien Amendola
  4. Jean-Marc Goaillard
(2014)
Non-linear developmental trajectory of electrical phenotype in rat substantia nigra pars compacta dopaminergic neurons
eLife 3:e04059.
https://doi.org/10.7554/eLife.04059

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https://doi.org/10.7554/eLife.04059

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