<unk>  (; or lenomorelin, INN) is a hormone produced by enteroendocrine cells of the gastrointestinal tract, especially the stomach, and is often called a "hunger hormone" because it increases the drive to eat. Blood levels of<unk>  are highest before meals when hungry, returning to lower levels after mealtimes.<unk>  may help prepare for food intake by increasing gastric motility and stimulating the secretion of gastric acid.<unk>  activates cells in the anterior pituitary gland and hypothalamic arcuate nucleus, including neuropeptide Y neurons that initiate appetite.<unk>  stimulates brain structures having a specific receptor – the growth hormone secretagogue receptor 1A (GHSR-1A).<unk>  also participates in regulation of reward cognition, learning and memory, the sleep-wake cycle, taste sensation, reward behavior, and glucose metabolism.
Ghrelin
Histrelin
Nesfatin-1
Incretin
Somatostatin
Agouti-related peptide
Glucagon-like peptide-1
Orexin