The food-entrainable oscillator: a network of interconnected brain structures entrained by humoral signals?
Food is critical for all animal species. Its temporal availability is a relevant signal for organizing behavioral and physiological parameters. When food is restricted to a few hours per day, rats, mice, and other mammals exhibit anticipatory activity before mealtime (food-anticipatory activity). There is considerable evidence suggesting that this anticipation is mediated by a food-entrainable oscillator (FEO) with circadian properties, but located outside the suprachiasmatic nucleus of the hypothalamus (the light-entrainable oscillator). However, the locus of the FEO as well as the mechanisms by which food entrainment occurs is unclear. In this review, we summarize data about the potential input pathways to the FEO and propose a model for understanding it as a network of interconnected brain structures entrained by fluctuation of different humoral signals.
Carneiro
Breno Tercio Santos
BT
Centre for Biological Timing and Cognition, University of Toronto, Ontario, Canada. brenotercio@cb.ufrn.br
Araujo
John Fontenele
JF
D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001921:Brain / Q000502:physiology*; D002940:Circadian Rhythm / Q000502:physiology*; D005247:Feeding Behavior / Q000502:physiology*; D005502:Food; D054439:Ghrelin / Q000502:physiology; D005934:Glucagon / Q000502:physiology; D007328:Insulin / Q000502:physiology; D020738:Leptin / Q000502:physiology; D051379:Mice; D008959:Models, Neurological; D009434:Neural Pathways / Q000502:physiology; D017440:Photoperiod; D051381:Rats; D015398:Signal Transduction; D013493:Suprachiasmatic Nucleus / Q000502:physiology; D014630:Vagus Nerve / Q000502:physiology
D001786:Blood Glucose; D054439:Ghrelin; D007328:Insulin; D020738:Leptin; D005934:Glucagon