Gastrointestinal hormones and regulation of gastric emptying

Purpose of review This review examines the hormonal regulation of gastric emptying, a topic of increasing relevance, given the fact that medications that are analogs of some of these hormones or act as agonists at the hormonal receptors, are used in clinical practice for optimizing metabolic control in the treatment of type 2 diabetes and in obesity. Recent findings The major effects on gastric emptying result from actions of incretins, particularly gastric inhibitory polypeptide, glucagon-like peptide-1, and peptide tyrosine-tyrosine, the duodenal and pancreatic hormones, motilin, glucagon, and amylin, and the gastric orexigenic hormones, ghrelin and motilin. All of these hormones delay gastric emptying, except for ghrelin and motilin which accelerate gastric emptying. These effects on gastric emptying parallel the effects of the hormones on satiation (by those retarding emptying) and increase appetite by those that accelerate emptying. Indeed, in addition to the effects of these hormones on hypothalamic appetite centers and glycemic control, there is evidence that some of their biological effects are mediated through actions on the stomach, particularly with the glucagon-like peptide-1 analogs or agonists used in treating obesity. Effects of gastrointestinal hormones on gastric emptying are increasingly recognized as important mediators of satiation and postprandial glycemic control.