Double-marker Technique Research Articles

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.

Fate of Oral Neutralizing Antacid and Its Effect on Postprandial Gastric Secretion and Emptying

The fate and neutralizing efficiency of oral antacids (aluminum and magnesium hydroxides) as well as their effect on postprandial gastric function were quantified in 6 patients with duodenal ulcer disease. We employed a double-marker technique for measurement of gastric secretion and emptying and combined this with back-titration of the gastric samples and analysis of aluminum to trace the fate of antacid in the stomach and duodenum. These studies show that: (a) antacid therapy with aluminum and magnesium hydroxides significantly increases gastric secretion; (b) intragastric neutralization of gastric acid produces a significant and substantial decrease in net acid output (acid secreted minus acid neutralized), but the beneficial effects of neutralization are partially offset by incomplete intragastric formation of aluminum trichloride; (c) most but not all of the ingested antacid is utilized in acid neutralization in the stomach (average 78.6% in our 6 patients); and (d) antacid therapy does not modify the absolute rate of postprandial gastric emptying, but increases dilution of gastric contents, expanding the intragastric volume. Thus, the fractional gastric emptying rate declines, and this, in turn, should enhance antacid utilization by delaying its emptying.