User:Signimu/Ghrelin2

Ghrelin (pronounced /ˈɡrɛlɪn/), is a circulating hormone produced by enteroendocrine cells of the gastrointestinal tract, especially the stomach, and is often called a "hunger" hormone because it increases food intake. Blood levels of ghrelin are highest before meals when hungry, returning to lower levels after mealtimes. Ghrelin may help prepare for food intake by increasing gastric motility as well as gastric acid secretion. Ghrelin can access the brain where it activates cells in the arcuate nucleus of the hypothalamus, including the orexigenic neuropeptide Y neurones that co-express agouti-related peptide (AgRP). Ghrelin's effects on food intake involve direct effects on hypothalamic, brainstem and forebrain areas and involve a dedicate receptor, the growth hormone secretagogue receptor 1A (GHSR-1A), whose brain distribution has been extensively mapped.