Our aim was to determine the role of intrinsic myoneural and enteric luminal continuity in the coordination of gastric and duodenal motility patterns. Three groups of dogs were prepared: five dogs with an intact gastrointestinal tract served as a Control group; four dogs had transection and reanastomosis of the duodenum 0.5 cm distal to the pylorus (Pyloric Transection group); and seven dogs had identical proximal duodenal transection, but with oversewing of duodenum and pylorojejunostomy to a Roux-en-Y limb (Roux-en-Y group). In the Control and Pyloric Transection groups, the gastric and intestinal MMCs were similar in appearance, the cycle durations (x +/- SEM) were not different (134 +/- 19 vs 111 +/- 26 min, respectively; P > 0.05), and the times between the start of gastric and duodenal Phase III (gastroduodenal latency) were similar (6 +/- 1 vs 10 +/- 3 min; P > 0.05). In the Roux-en-Y group, MMCs also occurred in six of seven dogs but tended to have a longer cycle duration (176 +/- 19 min) and a more variable gastroduodenal latency (23 +/- 15 min). Plasma motilin concentration, measured only in the Roux-en-Y group, was greater during Phase III in the stomach and duodenum than during Phases I or II (P < 0.05). Feeding inhibited the gastric and duodenal MMCs in all groups, but the duodenal MMC returned earlier in the Roux-en-Y group. The Roux-en-Y jejunal limb exhibited a postprandial pattern in only seven of 14 studies.(ABSTRACT TRUNCATED AT 250 WORDS)