title: Circadian rhythms of hedonic drinking behavior in mice.
abstract: In mammals, the suprachiasmatic nucleus (SCN) of the hypothalamus is the site of the main circadian clock, synchronized by the light-dark cycle, which generates behavioral rhythms like feeding, drinking and activity. Notwithstanding, the main role of the SCN clock on the control of all circadian rhythms has been questioned due to the presence of clock activity in many brain areas, including those implicated in the regulation of feeding and reward. Moreover, whether circadian rhythms of particular motivated behaviors exist is unknown. Here, we evaluated the spontaneous daily and circadian behavior of consumption of a sweet caloric solution (5-10% sucrose), and the effects of sucrose intake on the expression of clock genes in the mouse brain. Mice showed a daily (in a light-dark cycle) and a circadian (in constant darkness conditions) rhythm in the intake and sucrose preference with a rise for both parameters at night (or subjective night). In addition, we observed changes in the circadian day-night expression of the clock gene Per2 in the SCN, cortex and striatum of animals ingesting sucrose compared to control mice on pure water. Finally, daily rhythms of sucrose intake and preference were abolished in Per2Brdm1- and double Per1-/-Per2Brdm1-mutant animals. These data indicate that the expression of circadian rhythms of hedonic feeding behaviors may be controlled by brain circadian clocks and Per gene expression.
authors.affiliation: Institute of Cellular and Integrative Neurosciences, CNRS UPR-3212, University of Strasbourg, Strasbourg, France.
authors.forename: Claire
authors.initials: C
authors.lastname: Bainier
authors.affiliation: Institute of Cellular and Integrative Neurosciences, CNRS UPR-3212, University of Strasbourg, Strasbourg, France.
authors.forename: Maria
authors.initials: M
authors.lastname: Mateo
authors.affiliation: Institute of Cellular and Integrative Neurosciences, CNRS UPR-3212, University of Strasbourg, Strasbourg, France.
authors.forename: Marie-Paule
authors.initials: MP
authors.lastname: Felder-Schmittbuhl
authors.affiliation: Institute of Cellular and Integrative Neurosciences, CNRS UPR-3212, University of Strasbourg, Strasbourg, France. Electronic address: jmendoza@inci-cnrs.unistra.fr.
authors.forename: Jorge
authors.initials: J
authors.lastname: Mendoza
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D057906:Circadian Clocks / Q000502:physiology*; D002940:Circadian Rhythm / Q000502:physiology*; D004327:Drinking Behavior / Q000502:physiology*; D005247:Feeding Behavior / Q000502:physiology*; D008810:Mice, Inbred C57BL; D009043:Motor Activity / Q000502:physiology; D009687:Nuclear Proteins / Q000378:metabolism; D056950:Period Circadian Proteins / Q000378:metabolism; D013493:Suprachiasmatic Nucleus / Q000502:physiology*; D014157:Transcription Factors / Q000378:metabolism
chemical_list: D009687:Nuclear Proteins; D056950:Period Circadian Proteins; D014157:Transcription Factors
keywords: Per genes; circadian; drinking; motivation; reward; sucrose