Our aim was to determine if the pancreas regulates the interdigestive motor patterns of the upper gut. Four dogs were prepared with gastric and intestinal manometry catheters and interdigestive (fasting) motility was measured before and after total surgical pancreatectomy. The characteristics of the gastric and intestinal migrating motor complex were very similar before and after pancreatectomy. The time intervals between successive migrating motor complexes in the antrum (145 +/- 11 vs. 135 +/- 15 min, mean +/- SE) or small intestine (133 + 10 vs. 137 +/- 16 min) were not significantly (p greater than 0.4) altered by pancreatectomy, but the antral motility index (the sum of the antral contractions in a 15-min period) was greater after pancreatectomy (53 +/- 6 vs. 27 +/- 4; p less than 0.05). Pancreatectomy led to undetectable plasma concentrations of pancreatic polypeptide, but had no effect on absolute concentrations of plasma motilin or on the cycling of plasma motilin in association with the duodenal migrating motor complex. We conclude that the pancreas and pancreatic polypeptide play little, if any, role in controlling canine interdigestive motility of the upper gut.