Dorsal raphe nucleus to anterior cingulate cortex 5-HTergic neural circuit modulates consolation and sociability
Abstract
Consolation is a common response to the distress of others in humans and some social animals, but the neural mechanisms underlying this behavior are not well characterized. By using socially monogamous mandarin voles, we found that optogenetic or chemogenetic inhibition of 5-HTergic neurons in the dorsal raphe nucleus (DR) or optogenetic inhibition of 5-HT terminals in the anterior cingulate cortex (ACC) significantly decreased allogrooming time in the consolation test and reduced sociability in the three-chamber test. The release of 5-HT within the ACC and the activity of DR neurons were significantly increased during allogrooming, sniffing and social approaching. Finally, we found that the activation of 5-HT1A receptors in the ACC was sufficient to reverse consolation and sociability deficits induced by the chemogenetic inhibition of 5-HTergic neurons in the DR. Our study provided first direct evidence that DR-ACC 5-HTergic neural circuit is implicated in consolation-like behaviors and sociability.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. We had also deposited the datasets of this manuscript into the Dyrad.
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Dorsal raphe nucleus to anterior cingulate cortex 5-HTergic neural circuit modulates consolation and sociabilityDryad Digital Repository, doi:10.5061/dryad.8931zcrq7.
Article and author information
Author details
Funding
National Natural Science Foundation of China (31970424,31670421,31372213 and 31772473)
- Fa-Dao Tai
Natural Science Basic Research Program of Shaanxi Province (2018JM3032)
- Fa-Dao Tai
Fundamental Research Funds for the Central Universities (GK201903059)
- Fa-Dao Tai
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 the breeding, housing, and experimental procedures in this study were in accordance with Chinese guidelines for the care and use of laboratory animals and were approved by the Animal Care and Use Committee of Shaanxi Normal University (SNNU_20190501001). All efforts were made to minimize suffering and the number of animals used during the studies.
Copyright
© 2021, Li 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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