Abstract

Functional diversity of midbrain dopamine (DA) neurons ranges across multiple scales, from differences in intrinsic properties and connectivity to selective task engagement in behaving animals. Distinct in vitro biophysical features of DA neurons have been associated with different axonal projection targets. However, it is unknown how this translates to different firing patterns of projection-defined DA subpopulations in the intact brain. We combined retrograde tracing with single-unit recording and labelling in mouse brain to create an in vivo functional topography of the midbrain DA system. We identified differences in burst firing among DA neurons projecting to dorsolateral striatum. Bursting also differentiated DA neurons in the medial substantia nigra (SN) projecting either to dorsal or ventral striatum. We found differences in mean firing rates and pause durations among ventral tegmental area (VTA) DA neurons projecting to lateral or medial shell of nucleus accumbens. Our data establishes a high-resolution functional in vivo landscape of midbrain DA neurons.

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All data generated or analysed during this study are included in the manuscript and supporting files.

Article and author information

Author details

  1. Navid Farassat

    Institute for Neurophysiology, Goethe University Frankfurt, Frankfurt, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. ​Kauê Machado Costa

    Institute for Neurophysiology, Goethe University Frankfurt, Frankfurt, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5562-6495
  3. Strahinja Stovanovic

    Institute for Neurophysiology, Goethe University Frankfurt, Frankfurt, Germany
    Competing interests
    The authors declare that no competing interests exist.
  4. Stefan Albert

    Institute for Mathematics, Goethe University Frankfurt, Frankfurt, Germany
    Competing interests
    The authors declare that no competing interests exist.
  5. Lora Kovacheva

    Institute for Neurophysiology, Goethe University Frankfurt, Frankfurt, Germany
    Competing interests
    The authors declare that no competing interests exist.
  6. Josef Shin

    Institute for Neurophysiology, Goethe University Frankfurt, Frankfurt, Germany
    Competing interests
    The authors declare that no competing interests exist.
  7. Richard Egger

    Institute for Neurophysiology, Goethe University Frankfurt, Frankfurt, Germany
    Competing interests
    The authors declare that no competing interests exist.
  8. Mahalakshmi Somayaji

    Institute for Neurophysiology, Goethe University Frankfurt, Frankfurt, Germany
    Competing interests
    The authors declare that no competing interests exist.
  9. Sevil Duvarci

    Institute for Neurophysiology, Goethe University Frankfurt, Frankfurt, Germany
    Competing interests
    The authors declare that no competing interests exist.
  10. Gaby Schneider

    Institute for Mathematics, Goethe University Frankfurt, Frankfurt, Germany
    Competing interests
    The authors declare that no competing interests exist.
  11. Jochen Roeper

    Institute for Neurophysiology, Goethe University Frankfurt, Frankfurt, Germany
    For correspondence
    roeper@em.uni-frankfurt.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2145-8742

Funding

National Institutes of Health (R01DA041705)

  • Jochen Roeper

Deutsche Forschungsgemeinschaft (CRC 1080)

  • Jochen Roeper

Gutenberg Forschungskolleg

  • Jochen Roeper

Deutsche Forschungsgemeinschaft (CRC 1193)

  • Jochen Roeper

Deutsche Forschungsgemeinschaft (DFG Priority Program 1665 (SCHN 1370/02-1))

  • Gaby Schneider

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

Reviewing Editor

  1. Olivier J Manzoni, Aix-Marseille University, INSERM, INMED, France

Ethics

Animal experimentation: All experiments and procedures involving mice were approved by the German Regierungspräsidium Darmstadt (V54-19c20/15-F40/28).

Version history

  1. Received: May 13, 2019
  2. Accepted: October 2, 2019
  3. Accepted Manuscript published: October 3, 2019 (version 1)
  4. Version of Record published: October 14, 2019 (version 2)

Copyright

This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

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  1. Navid Farassat
  2. ​Kauê Machado Costa
  3. Strahinja Stovanovic
  4. Stefan Albert
  5. Lora Kovacheva
  6. Josef Shin
  7. Richard Egger
  8. Mahalakshmi Somayaji
  9. Sevil Duvarci
  10. Gaby Schneider
  11. Jochen Roeper
(2019)
In vivo functional diversity of midbrain dopamine neurons within identified axonal projections
eLife 8:e48408.
https://doi.org/10.7554/eLife.48408

Share this article

https://doi.org/10.7554/eLife.48408

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