title: Ghrelin increases intake of rewarding food in rodents.
abstract: We investigated whether ghrelin action at the level of the ventral tegmental area (VTA), a key node in the mesolimbic reward system, is important for the rewarding and motivational aspects of the consumption of rewarding/palatable food. Mice with a disrupted gene encoding the ghrelin receptor (GHS-R1A) and rats treated peripherally with a GHS-R1A antagonist both show suppressed intake of rewarding food in a free choice (chow/rewarding food) paradigm. Moreover, accumbal dopamine release induced by rewarding food was absent in GHS-R1A knockout mice. Acute bilateral intra-VTA administration of ghrelin increased 1-hour consumption of rewarding food but not standard chow. In comparison with sham rats, VTA-lesioned rats had normal intracerebroventricular ghrelin-induced chow intake, although both intake of and time spent exploring rewarding food was decreased. Finally, the ability of rewarding food to condition a place preference was suppressed by the GHS-R1A antagonist in rats. Our data support the hypothesis that central ghrelin signaling at the level of the VTA is important for the incentive value of rewarding food.
authors.affiliation: Department of Physiology/Endocrinology, The Sahlgrenska Academy at the University of Gothenburg, SE-405 30 Gothenburg, Sweden. emil.egecioglu@medic.gu.se
authors.forename: Emil
authors.initials: E
authors.lastname: Egecioglu
authors.forename: Elisabet
authors.initials: E
authors.lastname: Jerlhag
authors.forename: Nicolas
authors.initials: N
authors.lastname: Salomé
authors.forename: Karolina P
authors.initials: KP
authors.lastname: Skibicka
authors.forename: David
authors.initials: D
authors.lastname: Haage
authors.forename: Mohammad
authors.initials: M
authors.lastname: Bohlooly-Y
authors.forename: Daniel
authors.initials: D
authors.lastname: Andersson
authors.forename: Mikael
authors.initials: M
authors.lastname: Bjursell
authors.forename: Daniel
authors.initials: D
authors.lastname: Perrissoud
authors.forename: Jörgen A
authors.initials: JA
authors.lastname: Engel
authors.forename: Suzanne L
authors.initials: SL
authors.lastname: Dickson
mesh_terms: D000818:Animals; D003214:Conditioning, Classical / Q000187:drug effects; D004298:Dopamine / Q000378:metabolism; D004435:Eating / Q000187:drug effects*; D054439:Ghrelin / Q000494:pharmacology*; D007267:Injections; D008032:Limbic System / Q000187:drug effects*; D008297:Male; D008636:Mesencephalon / Q000187:drug effects*; D051379:Mice; D018345:Mice, Knockout; D009434:Neural Pathways / Q000187:drug effects*; D009714:Nucleus Accumbens / Q000187:drug effects; D054440:Receptors, Ghrelin / Q000187:drug effects / Q000235:genetics; D012201:Reward; D015398:Signal Transduction / Q000187:drug effects; D013649:Taste / Q000187:drug effects; D017557:Ventral Tegmental Area / Q000187:drug effects*
chemical_list: D054439:Ghrelin; D054440:Receptors, Ghrelin; D004298:Dopamine