Duodenogastric reflux in the dog.

Duodenogastric reflux, gastric emptying, and gastric secretion were measured simultaneously by a double-marker technique after instillation of a liquid lipid meal (300 ml Intralipid) or a protein meal (300 ml Bactopeptone) in five trained mongrel dogs. A lipid meal was emptied slower and elicited less volume secretion than a protein meal. Duodenogastric reflux rate and intragastric accumulation of duodenal contents were similar with both meals. Intravenous infusion of atropine slowed gastric emptying and inhibited gastric volume secretion only in the case of protein meal. Atropine increased duodenogastric reflux rate and gastric accumulation of duodenal contents with both protein and lipid meals. The percentage of duodenal contents inside the stomach increased continuously during gastric emptying; it did not exceed 20% with both meals given alone and 40% with both meals given together with atropine. It is concluded that duodenogastric reflux and gastric accumulation of duodenal contents are common phenomena during gastric digestion of a meal. The degree of such accumulation does not depend on the type of meal. Intragastric accumulation of duodenal contents is increased when duodenogastric reflux rate is stimulated and when gastric emptying rate is inhibited simultaneously.