Activation of Serotonin 2C Receptors in Dopamine Neurons Inhibits Binge-like Eating in Mice.
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ABSTRACT: Background
Neural networks that regulate binge eating remain to be identified, and effective treatments for binge eating are limited.Methods
We combined neuroanatomic, pharmacologic, electrophysiological, Cre-lox, and chemogenetic approaches to investigate the functions of 5-hydroxytryptamine (5-HT) 2C receptor (5-HT2CR) expressed by dopamine (DA) neurons in the regulation of binge-like eating behavior in mice.Results
We showed that 5-HT stimulates DA neural activity through a 5-HT2CR-mediated mechanism, and activation of this midbrain 5-HT→DA neural circuit effectively inhibits binge-like eating behavior in mice. Notably, 5-HT medications, including fluoxetine, d-fenfluramine, and lorcaserin (a selective 5-HT2CR agonist), act on 5-HT2CRs expressed by DA neurons to inhibit binge-like eating in mice.Conclusions
We identified the 5-HT2CR population in DA neurons as one potential target for antibinge therapies, and provided preclinical evidence that 5-HT2CR agonists could be used to treat binge eating.
SUBMITTER: Xu P
PROVIDER: S-EPMC5148733 | biostudies-literature |
REPOSITORIES: biostudies-literature
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