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Publication"The dorsomedial hypothalamic nucleus is critical for the expression of food-entrainable circadian rhythms", Nature Neuroscience
March 1, 2006
Authors Joshua J. Gooley, Ashley Shomer and Clifford B. Saper published an important article, "The dorsomedial hypothalamic nucleus is critical for the expression of food-entrainable circadian rhythms", in Nature Neuroscience in March 2006 describing for the first time the role of the dorsomedial nucleus of the hypothalamus in providing a timing signal that can drive circadian rhythms based upon food availability. The authors found that when the rats were placed in an environment where food was only available during their normal sleep period, they flipped their circadian rhythms of wake-sleep, body temperature, and activity to be awake a few hours before the food appeared. First author Dr. Gooley found that the DMH was necessary for the brain to override the biological clock in the suprachiasmatic nucleus.
Citation:
Gooley JJ, Schomer A, Saper CB. The dorsomedial hypothalamic nucleus is critical for the expression of food-entrainable circadian rhythms.
Nat Neurosci. 2006 Mar;9(3):398-407. Epub 2006 Feb 19. PMID: 16491082
Abstract:
Circadian rhythms of behavior and physiology can be entrained by daily cycles of restricted food availability, but the pathways that mediate food entrainment are unknown. The dorsomedial hypothalamic nucleus (DMH) is critical for the expression of circadian rhythms and receives input from systems that monitor food availability. Here we report that restricted feeding synchronized the daily rhythm of DMH activity in rats such that c-Fos expression in the DMH was highest at scheduled mealtime. During food restriction, unlesioned rats showed a marked preprandial rise in locomotor activity, body temperature and wakefulness, and these responses were blocked by cell-specific lesions in the DMH. Furthermore, the degree of food entrainment correlated with the number of remaining DMH neurons, and lesions in cell groups surrounding the DMH did not block entrainment by food. These results establish that the neurons of the DMH have a critical role in the expression of food-entrainable circadian rhythms.
Citation:
Gooley JJ, Schomer A, Saper CB. The dorsomedial hypothalamic nucleus is critical for the expression of food-entrainable circadian rhythms.
Nat Neurosci. 2006 Mar;9(3):398-407. Epub 2006 Feb 19. PMID: 16491082
Abstract:
Circadian rhythms of behavior and physiology can be entrained by daily cycles of restricted food availability, but the pathways that mediate food entrainment are unknown. The dorsomedial hypothalamic nucleus (DMH) is critical for the expression of circadian rhythms and receives input from systems that monitor food availability. Here we report that restricted feeding synchronized the daily rhythm of DMH activity in rats such that c-Fos expression in the DMH was highest at scheduled mealtime. During food restriction, unlesioned rats showed a marked preprandial rise in locomotor activity, body temperature and wakefulness, and these responses were blocked by cell-specific lesions in the DMH. Furthermore, the degree of food entrainment correlated with the number of remaining DMH neurons, and lesions in cell groups surrounding the DMH did not block entrainment by food. These results establish that the neurons of the DMH have a critical role in the expression of food-entrainable circadian rhythms.
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