Rate of transient lower oesophageal sphincter relaxations of healthy humans after eating a mixed nutrient meal : time course and comparison with fasting

Objective: To assess the time course of the rate (n/30 min) of transient lower oesophageal sphincter relaxations (TLOSRs) after a meal and to compare results with the fasting rate in healthy subjects. Design: Oesophageal motility was recorded in eight healthy volunteers for 30 min before and 2h after a 700kcal homogenized mixed nutrient meal. Methods: An assembly of polyvinyl tubes incorporating a sleeve sensor was used. The observation period was made up of five 30-min epochs: fasting and 0-30, 30-60, 60-90 and 90-120 min after eating. Differences among epochs were assessed by non-parametric analysis of variance followed by Newman-Keuls test for multiple comparisons. Results: Ingestion of the meal significantly (P<0.01) increased the rate of TLOSRs from 1.0; 0-2.5 (median; interquartile range) in fasting to 4.5; 3.0-5.0 in the 0-30 min epoch. However, the increase was not sustained, the rate declining progressively to 3.5; 2.5-5.0 in the 30-60 min epoch, 3.5; 2.0-5.0 in the 60-90 min epoch and 1.5; 1.0-2.0 in the 90-120 min epoch (respectively, P<0.05, P<0.05 and P = NS versus fasting). Conclusions: In healthy man, eating a meal is an effective stimulus to increase the rate of TLOSRs. However, the stimulation may be short-lived suggesting that, in research protocols using a meal as stimulus for TLOSRs, only one experimental condition should be tested on each study day.