Relation between antral motility and gastric emptying of solids and liquids in humans

Our aim was to test the hypothesis that there is a relation between antral phasic pressure activity and the emptying of solids and liquids from the intact human stomach after a mixed meal. This hypothesis was evaluated in 14 healthy individuals in whom we performed simultaneous antral manometry and radioscintigraphy after ingestion of a meal labeled with [99mTc]sulfur colloid in cooked egg (solid component) and [111In]DTPA (liquid component). Analysis of the data included an in-depth evaluation of different models for expressing both gastric emptying rates and antral pressure activity. We found that gastric emptying was adequately represented by a two-phase model consisting of lag and emptying periods and by a power exponential model for the liquid phase. Distal antral motility was accurately represented by the slope of the cumulative antral motility index. During the lag period for solids, the antral motility was inversely related to the duration of the lag. During the solid-emptying period, there was a positive correlation between emptying of solids and antral motility. No significant relation was found between antral motility and overall emptying of the liquid phase of the meal. However, a relationship was found when antral motility was related to liquid emptying after an initial lag period for solids. These human data are consistent with a role of antral pressure activity in trituration of solid food and a role of the antrum in the subsequent propulsion of solids and liquids from the stomach.