peptones and Fistula

The present study was done to investigate the factors regulating the intestinal phase of exocrine pancreatic secretion in the turkey. The intestine of turkeys equipped with pancreatic fistulas was perfused with peptone solution, fat emulsion and hydrochloric acid (HCl), and pancreatic flow and protein output were measured. Neither peptone solution nor fat emulsion had any effects on pancreatic secretion. HCl enhanced the flow rate of pancreatic juice but not protein output. To clarify the neural mechanism of this phenomenon, the vagal postganglionic blocker atropine was continuously infused and pancreatic secretion in response to intestinal HCl was measured. Atropine completely suppressed both pancreatic flow and protein output. It is suggested that the avian intestinal phase of pancreatic secretion is mainly controlled by cholinergic action though HCl stimulation.

Topics: Animals; Atropine; Dietary Fats; Emulsions; Fistula; Hydrochloric Acid; Intestines; Kinetics; Pancreas; Pancreatic Juice; Peptones; Perfusion; Time Factors; Turkeys

Neural and endocrine pathways mediate the inhibitory effects of intestinal fat on gastric acid secretion. To study whether vagal and/or spinal afferent nerves contribute to the neural component of the enterogastric reflex, the sensory neurotoxin capsaicin was applied topically either to the vagus nerves bilaterally or to the celiac-superior mesenteric ganglia in rats with chronic gastric and duodenal fistulas. In lightly restrained, awake rats acid secretion was stimulated for 2 h by continuous intragastric perfusion with 8% peptone and was measured by extragastric titration to pH 5.5. Duodenal lipid perfusion (0-20%) during the 2nd h caused inhibition of peptone-stimulated acid output. Acid output was inhibited by 81% during 5% lipid perfusion of the duodenum and was restored after capsaicin treatment of the vagus nerves. In contrast, capsaicin treatment of the celiac ganglion did not alter the acid inhibitory response to any dose of intestinal lipid. Basal and maximum acid outputs were not significantly different among rats treated by either method with capsaicin. The neural component of the enterogastric reflex in awake rats is mediated in part by a capsaicin-sensitive, vagal-afferent neural reflex.

Topics: Afferent Pathways; Animals; Capsaicin; Duodenum; Fistula; Ganglia, Sympathetic; Gastric Acid; Gastric Mucosa; Lipids; Male; Peptones; Perfusion; Rats; Rats, Sprague-Dawley; Vagus Nerve

The role of the duodenum in the regulation of the lower esophageal sphincter pressure (LESP) was investigated in 4 unrestrained dogs equipped with a chronic Komarov type esophagostomy, a cutaneous duodenal fistula, a gastrojejunostomy, and a Y anastomosis between the distal end of the duodenum and the midjejunum. Installation of NaCl solution into the duodenum or into the stomach did not effect LESP during the following 60-min observation period. Peptone instillation into the duodenum or into the stomach produced a sustained elevation LESP. The rise of LESP was significantly greater after duodenal than after gastric instillation. Duodenal peptone did not raise serum gastrin. It is concluded that the duodenum may be an important regulator of LESP in the dog and that this effect is not mediated by circulating gastrin.

Topics: Animals; Dogs; Duodenum; Esophagogastric Junction; Esophagus; Fistula; Jejunum; Manometry; Peptones

1. Gastric acid response to a test meal of 10% peptone was measured in chronic gastric and pancreatic fistula cats using the Fordtran and Walsh method, monitoring the rate at which a solution of 0.5 M sodium bicarbonate had to be added to maintain constant pH of gastric content at pre-selected values ranging from 5.0 to 1.0. Simultaneously, pancreatic secretion was determined by the standard collection technique. In this way the pH profile for the inhibition of gastric secretion and stimulation of pancreatic secretion has been established in cats.2. A peptone meal adjusted to pH 5.0 produced gastric acid output similar to the maximal response to histamine or pentagastrin. It provoked a negligible stimulation of pancreatic flow rate and bicarbonate output but a large protein output.3. Graded decrease of the peptone meal pH to below 4.0 resulted in inhibition of gastric acid production and in a concomitant stimulation of pancreatic secretory volume and bicarbonate output. A meal adjusted to pH 1.0 stimulated gastric secretion only about 30% of the response recorded at pH 5.0. Pancreatic secretion with a meal adjusted to pH 3.0 reached the highest level of about 70% of the maximal response to exogenous secretin.4. Since the observed changes in the secretory activity of the stomach and the pancreas induced by test meals adjusted to pH 3.0 can be fully reproduced by exogenous secretin, it is suggested that in the cat this hormone may be responsible for the gastric inhibitory and pancreatic stimulatory mechanisms activated during normal digestion of food.

Topics: Animals; Cats; Fistula; Food; Gastric Juice; Gastric Mucosa; Hydrogen-Ion Concentration; Pancreas; Peptones; Secretin; Secretory Rate