Dopamine receptor 1 neurons in the dorsal striatum regulate food anticipatory circadian activity rhythms in mice
- California Institute of Technology, United States
- University of Washington, United States
- Claremont-McKenna College, Pitzer College, Scripps College, United States
- Simon Fraser University, Canada
- California State Polytechnic University Pomona, United States
- Howard Hughes Medical Institute, University of Washington, United States
Abstract
Daily rhythms of food anticipatory activity (FAA) are regulated independently of the suprachiasmatic nucleus, which mediates entrainment of rhythms to light, but the neural circuits that establish FAA remain elusive. Here we show that mice lacking the dopamine D1 receptor (D1R KO mice), manifest greatly reduced FAA, whereas mice lacking the dopamine D2 receptor have normal FAA. To determine where dopamine exerts its effect, we limited expression of dopamine signaling to the dorsal striatum of dopamine-deficient mice; these mice developed FAA. Within the dorsal striatum, the daily rhythm of clock gene per2 expression was markedly suppressed in D1R KO mice. Pharmacological activation of D1R at the same time daily was sufficient to establish anticipatory activity in wild-type mice. These results demonstrate that dopamine signaling to D1R in the dorsal striatum plays an important role in manifestation of FAA, possibly by synchronizing circadian oscillators that modulate motivational processes and behavioral output.
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Animal experimentation: This study was performed in accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocol 1567.
Copyright
© 2014, Gallardo 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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Dopamine receptor 1 neurons in the dorsal striatum regulate food anticipatory circadian activity rhythms in mice
eLife 3:e03781.
https://doi.org/10.7554/eLife.03781
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