title: Ghrelin and food reward: the story of potential underlying substrates.
abstract: The incidence of obesity is increasing at an alarming rate and this worldwide epidemic represents a significant decrease in life span and quality of life of a large part of the affected population. Therefore an understanding of mechanisms underlying food overconsumption and obesity development is urgent and essential to find potential treatments. Research investigating mechanisms underlying obesity and the control of food intake has recently experienced a major shift in focus, from the brain's hypothalamus to additional important neural circuits controlling emotion, cognition and motivated behavior. Among them, the mesolimbic system, and the changes in reward and motivated behavior for food, emerge as new promising treatment targets. Furthermore, there is also growing appreciation of the impact of peripheral hormones that signal nutrition status to the mesolimbic areas, and especially the only known circulating orexigenic hormone, ghrelin. This review article provides a synthesis of recent evidence concerning the impact of manipulation of ghrelin and its receptor on models of food reward/food motivation behavior and the mesolimbic circuitry. Particular attention is given to the potential neurocircuitry and neurotransmitter systems downstream of ghrelin's effects on food reward.
authors.affiliation: Department of Physiology/Endocrinology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Medicinaregatan 11, SE-405 30 Gothenburg, Sweden. karolina.skibicka@neuro.gu.se
authors.forename: Karolina P
authors.initials: KP
authors.lastname: Skibicka
authors.forename: Suzanne L
authors.initials: SL
authors.lastname: Dickson
mesh_terms: D000818:Animals; D001069:Appetite Regulation / Q000502:physiology*; D003071:Cognition; D059305:Diet, High-Fat / Q000009:adverse effects; D004298:Dopamine / Q000378:metabolism*; D004435:Eating / Q000187:drug effects / Q000502:physiology*; D005247:Feeding Behavior / Q000502:physiology; D005753:Gastric Mucosa / Q000378:metabolism; D015870:Gene Expression; D054439:Ghrelin / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008032:Limbic System / Q000187:drug effects / Q000378:metabolism*; D050356:Lipid Metabolism; D051379:Mice; D018345:Mice, Knockout; D009479:Neuropeptides / Q000235:genetics / Q000378:metabolism; D009765:Obesity / Q000378:metabolism* / Q000503:physiopathology; D054440:Receptors, Ghrelin / Q000235:genetics / Q000378:metabolism; D012201:Reward; D015398:Signal Transduction / Q000502:physiology*; D017557:Ventral Tegmental Area / Q000187:drug effects / Q000378:metabolism*
chemical_list: D054439:Ghrelin; D009479:Neuropeptides; D054440:Receptors, Ghrelin; D004298:Dopamine