title: Rapid sensing of circulating ghrelin by hypothalamic appetite-modifying neurons.
abstract: To maintain homeostasis, hypothalamic neurons in the arcuate nucleus must dynamically sense and integrate a multitude of peripheral signals. Blood-borne molecules must therefore be able to circumvent the tightly sealed vasculature of the blood-brain barrier to rapidly access their target neurons. However, how information encoded by circulating appetite-modifying hormones is conveyed to central hypothalamic neurons remains largely unexplored. Using in vivo multiphoton microscopy together with fluorescently labeled ligands, we demonstrate that circulating ghrelin, a versatile regulator of energy expenditure and feeding behavior, rapidly binds neurons in the vicinity of fenestrated capillaries, and that the number of labeled cell bodies varies with feeding status. Thus, by virtue of its vascular connections, the hypothalamus is able to directly sense peripheral signals, modifying energy status accordingly.
authors.affiliation: Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5203,  Institut de Génomique Fonctionnelle, F-34000 Montpellier,  France.
authors.forename: Marie
authors.initials: M
authors.lastname: Schaeffer
authors.forename: Fanny
authors.initials: F
authors.lastname: Langlet
authors.forename: Chrystel
authors.initials: C
authors.lastname: Lafont
authors.forename: François
authors.initials: F
authors.lastname: Molino
authors.forename: David J
authors.initials: DJ
authors.lastname: Hodson
authors.forename: Thomas
authors.initials: T
authors.lastname: Roux
authors.forename: Laurent
authors.initials: L
authors.lastname: Lamarque
authors.forename: Pascal
authors.initials: P
authors.lastname: Verdié
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Bourrier
authors.forename: Bénédicte
authors.initials: B
authors.lastname: Dehouck
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Banères
authors.forename: Jean
authors.initials: J
authors.lastname: Martinez
authors.forename: Pierre-François
authors.initials: PF
authors.lastname: Méry
authors.forename: Jacky
authors.initials: J
authors.lastname: Marie
authors.forename: Eric
authors.initials: E
authors.lastname: Trinquet
authors.forename: Jean-Alain
authors.initials: JA
authors.lastname: Fehrentz
authors.forename: Vincent
authors.initials: V
authors.lastname: Prévot
authors.forename: Patrice
authors.initials: P
authors.lastname: Mollard
mesh_terms: D000818:Animals; D001069:Appetite Regulation / Q000502:physiology*; D001812:Blood-Brain Barrier / Q000502:physiology; D002199:Capillary Permeability; D004435:Eating / Q000502:physiology; D005215:Fasting / Q000502:physiology; D054439:Ghrelin / Q000097:blood*; D007031:Hypothalamus / Q000098:blood supply / Q000166:cytology / Q000502:physiology*; D008297:Male; D008473:Median Eminence / Q000098:blood supply / Q000166:cytology / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D036641:Microscopy, Fluorescence, Multiphoton; D008959:Models, Neurological; D009474:Neurons / Q000502:physiology
chemical_list: D054439:Ghrelin