Roundabout receptor 2 maintains inhibitory control of the adult midbrain
- University of Washington, United Kingdom
- University of Washington, United States
- Boston University Medical Center, United States
Abstract
The maintenance of excitatory and inhibitory balance in the brain is essential for its function. Here we find that the developmental axon guidance receptor Roundabout 2 (Robo2) is critical for the maintenance of inhibitory synapses in the adult ventral tegmental area (VTA), a brain region important for the production of the neurotransmitter dopamine. Following selective genetic inactivation of Robo2 in the adult VTA of mice, reduced inhibitory control results in altered neural activity patterns, enhanced phasic dopamine release, behavioral hyperactivity, associative learning deficits, and a paradoxical inversion of psychostimulant responses. These behavioral phenotypes could be phenocopied by selective inactivation of synaptic transmission from local GABAergic neurons of the VTA, demonstrating an important function for Robo2 in regulating the excitatory and inhibitory balance of the adult brain.
Article and author information
Author details
Funding
National Institutes of Health (R01-MH094536)
- Larry S Zweifel
National Institute for Health Research (EY10699)
- Rachel O Wong
National Institute for Health Research (R01-DK078226)
- Weining Lu
National Institutes of Health (R01-MH104450)
- Larry S Zweifel
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 were done in accordance with a protocol (4249-01) approved by the University of Washington Animal Care and Use Committee.
Copyright
© 2017, Gore 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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Roundabout receptor 2 maintains inhibitory control of the adult midbrain
eLife 6:e23858.
https://doi.org/10.7554/eLife.23858
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