motilin Activators

Motilin is a peptide hormone, comprising 22 amino acids, predominantly produced by endocrine M cells in the upper small intestine, particularly the duodenum. It plays a critical role in the gastrointestinal (GI) motility, especially in the fasting state. Motilin orchestrates the migrating motor complex (MMC), a series of electromechanical activities that occur in a regular cycle every 1.5 to 2 hours during fasting. These movements are essential for propelling undigested residues through the GI tract and inhibiting bacterial overgrowth.

The secretion of motilin is pulsatile and increases in response to fasting, with levels peaking at regular intervals that correspond to the phases of the MMC. Its release is inhibited by the ingestion of food, particularly fats and acids. Motilin exerts its effects by binding to G-protein-coupled receptors on GI smooth muscle cells, stimulating contractions that facilitate the movement of contents through the stomach and small intestine.Beyond its prokinetic effects, motilin may also influence other physiological processes, such as stimulating pepsin production and enhancing gastric emptying. Motilin agonists, like erythromycin, have been used for conditions associated with reduced GI motility.