Fundic balloon distension stimulates antral and duodenal motility in man.

Distension of the intestine triggers the peristaltic reflex, which consists of orad contraction and aborad relaxation. Whether a similar response occurs in the human stomach is unclear. Our aim was to investigate the antral and duodenal motor response(s) to mechanical distension of the proximal stomach. In six healthy volunteers, a large compliant balloon was placed in the proximal stomach. Alongside this a water-perfused manometry probe with six sensors was placed to measure the antral and duodenal motility. Pressure activity was assessed before and during balloon distension. In five of six subjects, balloon distension triggered a salvo of antral pressure waves within 3-5 min, some of which propagated into the duodenum. The amplitude of waves was higher (P < 0.05) at the antrum than at the duodenum. The area under the curve of pressure waves was higher (P < 0.05) at the antrum than at the duodenum. In conclusion, distension of the proximal stomach, at or below the threshold for perception, evokes phasic motor activity in the antrum and duodenum. Thus, the gastric response to distension differs from that observed during the intestinal peristaltic reflex.