Stimulation of the small intestine by nutrients in relation to phase of the migrating motor complex.

BACKGROUND

The relationship between the preceding phase of the migrating motor complex (MMC) and postprandial motility in the small intestine was studied.

METHODS

In eight healthy subjects small-bowel manometry was performed, and a 55-ml caloric liquid bolus (280 kJ) containing paracetamol and 14C-D-xylose was instilled into the duodenum during phase I and late phase II of the intestinal MMC, respectively, in randomized order. Blood samples were drawn at regular intervals and analysed for insulin, gastrin, glucose, paracetamol, and 14C-D-xylose.

RESULTS

After bolus administration during late phase II a phase-III-like activity succeeded by quiescence occurred in the duodenum in seven of eight subjects, whereas administration during phase I initiated irregular contractions in seven of eight subjects (P < 0.05). The caloric bolus induced a significant increase in serum insulin and gastrin. Areas under the curves for serum insulin, gastrin, glucose, paracetamol, and 14C-D-xylose were not modulated by the preceding phase of the MMC.

CONCLUSIONS

The present study shows that a nutrient bolus instilled into the intestinal lumen induces MMC-like activity when administered during late phase II. These findings provide further evidence of interference between MMC and postprandial motility.