Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0847097 (acidity)
 15,165 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Gastric acidity is influenced by systemic and local peptide effects. Previous work by others has shown that intraluminally secreted peptides may have a role in local control of gastric acidity; however, the response of these peptides to acute changes in gastric pH is unknown. To determine the effects of acute changes in pH on systemic and intraluminal peptide levels, 14 normal volunteers underwent placement of a nasogastric tube after an overnight fast. Blood and gastric fluid were analyzed on a control day, 2 hours after completion of 24 hours of aluminum-magnesium antacid therapy and after 24 hours of H2 blockade. Plasma and acid-alcohol-extracted gastric peptide levels were measured with specific radioimmunoassays. Specimens were subdivided into two groups: 28 gastric fluid specimens with a pH less than 4 and 10 specimens with a pH greater than 4. In the patients with a pH greater than 4, the luminal peptides, motilin, neurotensin, pancreatic polypeptide, somatostatin, substance P, and gastrin, were decreased by 50% to 90% and gastrin-releasing peptide was decreased by 36% compared with specimens with a pH less than 4. Conversely, intraluminal vasoactive intestinal polypeptide and calcitonin levels were elevated by 60% and 27%, respectively, in the samples with a pH greater than 4. Intraluminal peptide concentrations are responsive to changes in intragastric pH; however, this response was not seen in plasma peptide levels.
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PMID:Acute gastric pH changes alter intraluminal but not plasma peptide levels. 172 Sep 3

Recently, intragastroduodenal acidity has been shown to play an important role in interdigestive gastrointestinal motility. In this study, gastrointestinal motility and intragastric pH changes were monitored simultaneously in dogs, to characterize 1) the relationship between intragastric pH changes and IMC, and 2) the effects of intragastric acidity on motilin-induced phase III contractions in the gastric antrum by using secretagogues and an H2 receptor antagonist (cimetidine). As a result, intragastric pH showed periodic changes with gastric IMC in conscious dogs. Furthermore, motilin-induced gastric phase III contractions were inhibited by gastric acidification. But inhibition of gastric acid secretion by cimetidine normalized both the motor index and migration of the contractions. In conclusion, gastric acid secretion may influence the sensitivity to motilin of the stomach, and play an important role in the regulation of interdigestive gastric motility.
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PMID:[Inhibition of gastric acid secretion normalizes interdigestive motor activity in the stomach in dogs]. 188 Sep 48

The patients with chronic superficial gastritis were selected in the study. The variation in gastric acidity output, serum gastrin and plasma somatostatin concentration were observed during the Saussurea lappa decoction (SLD) perfusion into the stomach. There was no significant changes in acidity output, serum gastrin and plasma somatostatin concentration after the perfusion of SLD (P > 0.05). Changes in gastric emptying and plasma motilin concentration were observed after oral administration of the SLD in 5 healthy volunteers. The time of gastric emptying was markedly shortened after oral administration of SLD (P < 0.01). A significant increase occurred in plasma motilin concentration at 30 min. after oral administration of SLD (P < 0.01). It revealed that SLD could accelerate the gastric emptying and increase the endogenous motilin release.
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PMID:[Effect of Saussurea lappa on gastric functions]. 795 Feb 25