Motilin binds to specific motilin receptors, which are G-protein-coupled receptors (GPCRs) found on the smooth muscle cells in the gastrointestinal tract. The primary function of motilin is to induce phase III of the MMC, a pattern of electromechanical activity observed in the gastrointestinal tract during fasting. This phase is characterized by strong, rhythmic contractions that help in clearing the gut of residual food, secretions, and debris, thus preparing it for the next meal.
