Activation of the dopaminergic pathway from VTA to the medial olfactory tubercle generates odor-preference and reward
- Wuhan Institute of Physics and Mathematics, China
- Wuhan University, China
- Shenzhen Institutes of Advanced Technology, China
- Wuhan National Laboratory for Optoelectronics, China
Abstract
Odor-preferences are usually influenced by life experiences. However, the neural circuit mechanisms remain unclear. The medial olfactory tubercle (mOT) is involved in both reward and olfaction, while the ventral tegmental area (VTA) dopaminergic (DAergic) neurons are considered to be engaged in reward and motivation. Here, we found that the VTA (DAergic)-mOT pathway could be activated by different types of naturalistic rewards as well as odors in DAT-cre mice. Optogenetic activation of the VTA-mOT DAergic fibers was able to elicit preferences for space, location and neutral odor, while pharmacological blockade of the dopamine receptors in the mOT fully prevented the odor-preference formation. Furthermore, inactivation of the mOT-projecting VTA DAergic neurons eliminated the previously formed odor-preference and strongly affected the Go-no go learning efficiency. In summary, our results revealed that the VTA (DAergic)-mOT pathway mediates a variety of naturalistic reward processes and different types of preferences including odor-preference in mice.
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Author details
Funding
Ministry of Science and Technology of the People's Republic of China (2015CB755600)
- Fuqiang Xu
Chinese Academy of Sciences (XDB02050005)
- Fuqiang Xu
National Natural Science Foundation of China (81661148053)
- Fuqiang Xu
National Natural Science Foundation of China (91632303)
- Fuqiang Xu
National Natural Science Foundation of China (31400945)
- Qing Liu
National Natural Science Foundation of China (31400946)
- Xiaoping Rao
National Natural Science Foundation of China (31400977)
- Xiaobin He
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 surgical and experimental procedures were conducted in accordance with the guidelines of the Animal Care and Use Committee at the Wuhan Institute of Physics and Mathematics, the Chinese Academy of Sciences (reference number: WIPM-(2014)39). All Animals were housed with their littermates in a dedicated housing room with a 12/12 h light/dark cycle. Food and water were available free unless specifically noted. During the surgery, every effort was made to minimize suffering.
Copyright
© 2017, Zhang 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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Activation of the dopaminergic pathway from VTA to the medial olfactory tubercle generates odor-preference and reward
eLife 6:e25423.
https://doi.org/10.7554/eLife.25423
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