Motilin is a peptide hormone involved in gastrointestinal motility regulation, fasting digestive patterns, migrating motor complex coordination, and communication within the enteric nervous system. Motilin functions primarily as a cyclic endocrine signal promoting organized gastrointestinal contractions between meals.
The hormone stimulates migrating motor complexes that sweep through the stomach and small intestine during fasting states, helping clear residual food particles, secretions, and microbial accumulation from the upper digestive tract. Motilin also contributes to regulation of gastric emptying, intestinal smooth muscle activity, and coordination between enteric neural signaling and digestive physiology. Through these actions, the hormone supports organized gastrointestinal housekeeping and fasting-related motility adaptation.
Motilin is produced mainly by endocrine M cells located within the upper small intestine, especially the duodenum and jejunum. The hormone is synthesized and released in cyclical patterns associated with fasting physiology.
Production rises during interdigestive periods and declines after food intake. This rhythmic secretion pattern helps coordinate recurring migrating motor complexes that occur approximately every ninety to one hundred twenty minutes during fasting conditions.
Motilin secretion is regulated mainly by fasting physiology, enteric nervous-system signaling, and cyclical gastrointestinal motility patterns. Food intake strongly suppresses release, while fasting conditions stimulate rhythmic secretion dynamics.
The hormone acts through motilin receptor systems linked to smooth muscle contraction pathways, enteric neural signaling networks, calcium mobilization, and gastrointestinal motility regulation. Vagal pathways and autonomic nervous-system communication also contribute to signaling activity. Through these integrated gastrointestinal-endocrine systems, motilin coordinates fasting motility patterns, digestive tract clearance, smooth muscle activity, and enteric physiological regulation.
Motilin coordinates interdigestive “housekeeping” contractions that clear the stomach and proximal small bowel.
