INVOLVEMENT OF CHOLECYSTOKININ, RECEPTORS IN TRANSIENT LOWER ESOPHAGEAL SPHINCTER RELAXATIONS TRIGGERED BY GASTRIC DISTENSION

Objective: Transient lower esophageal sphincter relaxations (TLESRs) a re the main mechanism underlying gastroesophageal reflux, In the prese nt study we evaluated the effect of loxiglumide, a specific cholecysto kinin, (CCK,)-receptor antagonist, on the occurrence of TLESRs evoked by gastric distension. Methods: Eight healthy subjects underwent esoph ageal manometry using a 10-lumen sleeve assembly during placebo or lox iglumide (10 mg/kg/h) in a randomized double-blind order. Gastric dist ension was induced by inflation of 400 mi of air. Results: Basal lower esophageal pressure (LESP) and swallow-induced relaxation were not af fected by loxiglumide. Loxiglumide significantly reduced the number of TLESRs, from 11.5 (5.8-18.3) to 6.0 (3.3-14.3) during the total recor ding period of 1 h, and from 5.5 (4.25-7.5) to 2.0 (0.5-6.8) during th e first 15 min. The number of common cavities was significantly decrea sed by loxiglumide, from 8.0 (4.0-20.0) to 5.0 (2.0-7.8), TLESRs repre sented the main mechanism (60% during placebo, 74% during loxiglumide) underlying common cavities, followed by swallow-induced relaxation, C onclusions: Loxiglumide significantly reduces the number of TLESRs tri ggered by gastric distension without interfering with swallow-related relaxation of the lower esophageal sphincter, suggesting the involveme nt of CCK, receptors in the reflex pathway mediating TLESRs, (Am J Gas troenterol 1998;93:1823-1828. (C) 1998 by Am. Cell. of Gastroenterolog y)