Background Motilin, a 22-amino acid residue gastrointestinal peptide, is released by the endocrine cells in the mucosa of the upper part of the small intestine. The peripheral function of motilin mainly involved the regulation of the migrating motor complex (MMC)-phase III of the gastrointestinal tract in interdigestive state. Early more than twenty years ago, the motilin-like immunoreactivity was found in the central nervous system (CNS), and the following studies and researches indicated that ...