Heterogeneous somatostatin-expressing neuron population in mouse ventral tegmental area

Elife. 2020 Aug 4:9:e59328. doi: 10.7554/eLife.59328.

Abstract

The cellular architecture of the ventral tegmental area (VTA), the main hub of the brain reward system, remains only partially characterized. To extend the characterization to inhibitory neurons, we have identified three distinct subtypes of somatostatin (Sst)-expressing neurons in the mouse VTA. These neurons differ in their electrophysiological and morphological properties, anatomical localization, as well as mRNA expression profiles. Importantly, similar to cortical Sst-containing interneurons, most VTA Sst neurons express GABAergic inhibitory markers, but some of them also express glutamatergic excitatory markers and a subpopulation even express dopaminergic markers. Furthermore, only some of the proposed marker genes for cortical Sst neurons were expressed in the VTA Sst neurons. Physiologically, one of the VTA Sst neuron subtypes locally inhibited neighboring dopamine neurons. Overall, our results demonstrate the remarkable complexity and heterogeneity of VTA Sst neurons and suggest that these cells are multifunctional players in the midbrain reward circuitry.

Keywords: GABA; dopamine; glutamate; midbrain; mouse; neuron subtypes; neuroscience; reward.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Electrophysiological Phenomena
  • Female
  • Gene Expression Profiling
  • Interneurons / metabolism
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Neurons / classification
  • Neurons / cytology
  • Neurons / metabolism*
  • Neurotransmitter Agents / metabolism
  • Somatostatin / biosynthesis*
  • Ventral Tegmental Area / cytology*
  • Ventral Tegmental Area / metabolism*

Substances

  • Neurotransmitter Agents
  • Somatostatin

Associated data

  • GEO/10.1038/s41586-018-0654-5

Grants and funding

The project was funded by the Academy of Finland (1278174 and 1317399), The Finnish National Agency for Education EDUFI, the Sigrid Juselius Foundation, and research grants MOE2015-T2-2-095 and MOE2017-T3-1-002 from the Singapore Ministry of Education. The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.