GASTROINTESTINAL HORMONES: Edited by H. Christian WeberExpression and physiology of opioid receptors in the gastrointestinal tractMosińska, Paula; Zielińska, Marta; Fichna, JakubAuthor Information Department of Biochemistry, Faculty of Medicine, Medical University of Lodz, Lodz, Poland Correspondence to Jakub Fichna, PhD, DSc, Department of Biochemistry, Faculty of Medicine, Medical University of Lodz, Mazowiecka 6/8, 92–215 Lodz, Poland. Tel: +48 42 272 57 07; fax: +48 42 272 56 94; e-mail: [email protected] Current Opinion in Endocrinology & Diabetes and Obesity: February 2016 - Volume 23 - Issue 1 - p 3-10 doi: 10.1097/MED.0000000000000219 Buy Metrics Abstract Purpose of review Stimulation of opioid receptors elicits analgesic effect not only in the central nervous system, but also in the gastrointestinal tract, where a high concentration of opioid receptors can be found within the enteric nervous system as well as muscular and immune cells. Along with antinociception, opioid receptors in the stomach and intestine relay signals crucial for secretory and motor gastrointestinal function. Recent findings The review focuses on the utility of opioid receptor antagonists, which is generally contributing to the management of postoperative ileus and opioid bowel dysfunction in chronic pain patients nonetheless, opioid receptor antagonists can also be useful in the treatment of irritable bowel syndrome and chronic idiopathic constipation. The study also discusses several antidiarrheal opioid agonists, as well as opioids and opioid mimetics encompassing the concept of ligand-biased agonism and truncated opioid receptor splice variants. Summary Good understanding of the localization and the role of opioid receptors is vital for regulation of various pathophysiological processes in the gastrointestinal tract and may simultaneously provide a tempting approach in eliminating adverse effects related to centrally acting opioids. Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved.