In vivo functional diversity of midbrain dopamine neurons within identified axonal projections
- Goethe University Frankfurt, Germany
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.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Kauê Machado Costa
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.
Ethics
Animal experimentation: All experiments and procedures involving mice were approved by the German Regierungspräsidium Darmstadt (V54-19c20/15-F40/28).
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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In vivo functional diversity of midbrain dopamine neurons within identified axonal projections
eLife 8:e48408.
https://doi.org/10.7554/eLife.48408
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