Antropyloroduodenal activity during gastric emptying of liquid meals in humans

The present study examines the possible roles of the pylorus and the proximal duodenum in the gastric emptying of two liquid meals in six healthy volunteers. Gastric emptying of a saline meal (150 mM) and an acid meal (120 mM hydrochloric acid) were measured by the double-sampling dye dilution technique while antroduodenal motility was monitored with a continuously perfused catheter system. Pyloric region pressures were measured with a Dent sleeve. The acid meal (t1/2 = 13.5 +/- 1.8 min) emptied significantly (P less than 0.01) slower than the saline meal (t1/2 = 3.5 +/- 0.7 min). This slowing in the emptying of the acid meal was associated with significant (P less than 0.05) increments in tonic pyloric activity and phasic contractions of the proximal duodenum. Thus the gastric emptying of liquid meals is a complex process involving all components of the gastroduodenal region.