Manometric demonstration of duodenal/jejunal motor function consistent with the duodenal brake mechanism

High-resolution manometric studies below the stomach are rare due to technical limitations of traditional manometry catheters. Consequently, specific motor patterns and their impact on gastric and small bowel function are not well understood. High-resolution manometry was used to record fed-state motor patterns in the antro-jejunal segment and relate these to fasting motor function.

Antro-jejunal pressures were monitored in 15 healthy females using fiber-optic manometry (72 sensors at 1 cm intervals) before and after a high-nutrient drink.

Postprandial motility showed a previously unreported transition point 18.8 cm (range 13-28 cm) beyond the antro-pyloric junction. Distal to the transition, a zone of non-propagating, repetitive pressure events (11.5 ± 0.5 cpm) were dominant in the fed state. We have named this activity, the duodeno-jejunal complex (DJC). Continuous DJC activity predominated, but nine subjects also exhibited intermittent clusters of DJC activity, 7.4 ± 4.9/h, lasting 1.4 ± 0.55 minutes, and 3.8 ± 1.2 minutes apart. DJC activity was less prevalent during fasting (3.6 ± 3.3/h; P = .04). 78% of fed and fasting state propagating antro-duodenal pressure events terminated proximally or at the transition point and were closely associated with DJC clusters.

High-resolution duodeno-jejunal manometry revealed a previously unrecognized transition point and associated motor pattern extending into the jejunum, consistent with the duodenal brake previously identified fluoroscopically. Timing suggests DJC activity is driven by chyme stimulating duodenal mucosal chemosensors. These findings indicate that the duodenum and proximal jejunum consists of two major functional motor regions.