Characteristics of postprandial duodenal motor patterns in dogs.

In this study special attention was paid to the characteristics of duodenal motility under the influence of various test meals. Closely spaced strain gauge transducers and a computerized method were used to analyze motor patterns of the duodenum and the adjacent jejunum. Compared with an acaloric meal, nutrients shortened the length of contraction spread in the duodenum from 5.2 +/- 1.0 to 3.8 +/- 0.5-2.8 +/- 0.6 cm and in the jejunum from 10.5 +/- 3.0 to 7.4 +/- 1.3-5.2 +/- 0.8 cm. Additionally, contraction frequency was reduced. Basic differences were found between duodenal and jejunal motility. They were most marked in absence of nutrients. The duodenal motor pattern was characterized by a lower contraction frequency (8.0 +/- 2.2 vs 11.1 +/- 1.8/min), a shorter length of contraction spread (5.2 +/- 1.0 vs 10.5 +/- 3.0 cm), and a higher incidence of stationary contractions (50% vs 34%). On the duodenal bulb 72% of contractions represented contraction waves, whereas in the mid-duodenum the predominant feature was stationary contractions (57%) promoting the mixing of chyme with secretions. The characteristic duodenal motor patterns might be related to special functions of the duodenum for transport and digestion.