Proximal portion of duodenum is exposed to intermittent pulses of gastric H(+) discharged by the stomach. This review summarizes the mechanisms of duodenal mucosal integrity, mainly the role of mucus-alkaline secretion and the mucous barrier protecting surface epithelium against gastric H(+). The mucous barrier protects the leaky duodenal epithelium against each pulse of gastric H(+), which pen...

The escape ofacid gastric secretions from thestomach, in certain circumstances, is potentially destructive to the mucosae of the oesophagus and the duodenum. In the duodenum the pyloric sphincter plays a part in controlling gastric emptying, and further protection from the harmful effects of acid is offered by inhibitory mechanisms stimulated by duodenal acidification (Johnston and Duthie, 1965...

The release and physiological actions of secretin on pancreatic exocrine secretion and gastric secretion of acid and motility are regulated by neuro-hormonal control. The release of secretin by duodenal acidification is mediated by a secretin releasing peptide (SRP). The release and action of SRP are neurally mediated depending on vagal afferent pathway. SRP activity in acid perfusate of the du...

introduction: in ramadan, healthy adult muslims are obliged to fast. prolonged fasting increase gastric acid and pepsin levels, which promote the risk of duodenal ulcer perforation (dup). effects of ramadan fasting on dup have not been thoroughly studied yet, and the limited number of studies investigating the impact of ramadan fasting on dup yielded discrepant results. this study aimed to eval...

Oral calcium carbonate (0-5 g, pH 9-4) increased serum gastrin and gastric acid output with slight but insignificant change in serum calcium. A similar rise in serum calcium during an intravenous infusion of calcium gluconate failed to increase serum gastrin and gastric acid output. Both intragastric calcium actions were abolished by acidification of the calcium carbonate solution (pH 1-0). The...