ABSTRACT
Helicobacter pylori infection has been linked with a number of gastrointestinal diseases, such as peptic ulcer disease, gastric mucosa-associated lymphoid tissue lymphoma and gastric cancer. This article reviews some of the evidence for these associations, and discusses the latest recommended indications for eradication therapy.
Subject(s)
Gastrointestinal Diseases/microbiology , Helicobacter Infections/complications , Helicobacter pylori , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Atrophy , Dyspepsia/microbiology , Gastroesophageal Reflux/microbiology , Humans , Lymphoma, B-Cell, Marginal Zone/microbiology , Peptic Ulcer/microbiology , Stomach/pathology , Stomach Neoplasms/microbiologyABSTRACT
BACKGROUND AND AIMS: The main goal of our study was to characterise the activity of BIM26226 as a peripheral gastrin releasing peptide (GRP) receptor antagonist in healthy human subjects and to determine if endogenous GRP is a physiological regulator of gastric acid secretion and gastrin release. METHODS: Our study consisted of three parts. In part I, subjects received saline or BIM26226 followed by graded doses of intravenous human GRP in a four period crossover design. In part II, subjects received BIM26226 or saline during oral meal ingestion or modified sham feeding. In part III, subjects received an acidified meal in the presence and absence of BIM26226 in a two period crossover design. In addition, gastrin and somatostatin mRNA were measured in biopsy specimens during saline and BIM26226 infusion. RESULTS: BIM26226 dose dependently inhibited GRP induced acid output. Acid secretion after oral liquid meal intake and sham feeding was significantly inhibited by BIM26226 (p<0.01) whereas plasma gastrin release remained unchanged. Gastrin and somatostatin mRNAs were not significantly different after saline or BIM26226. CONCLUSIONS: BIM26226 is a potent GRP antagonist in humans. Endogenous GRP may be a physiological regulator of gastric acid secretion. Gastrin release does not seem to be under the control of GRP.
Subject(s)
Bombesin/analogs & derivatives , Bombesin/pharmacology , Gastric Acid/metabolism , Gastrin-Releasing Peptide/physiology , Peptide Fragments/pharmacology , Adult , Analysis of Variance , Blotting, Northern , Cross-Over Studies , Dose-Response Relationship, Drug , Double-Blind Method , Eating/physiology , Gastric Acidity Determination , Gastrin-Releasing Peptide/antagonists & inhibitors , Gastrins/analysis , Humans , Male , Middle Aged , RNA, Messenger/analysis , Somatostatin/analysis , Statistics, NonparametricABSTRACT
BACKGROUND & AIMS: Gastrin-releasing peptide stimulates gastrin secretion but also inhibits its release via somatostatin. Exogenous gastrin-releasing peptide stimulates a greater increase in plasma gastrin concentrations in patients infected with Helicobacter pylori than in uninfected controls. Because this infection suppressed gastric mucosal somatostatin, we studied whether the increased gastrin response was a result of an abnormal response of the somatostatin cell. METHODS: Patients without dyspeptic ulcers received an infusion of either gastrin-releasing peptide or saline on separate occasions. Acid secretion was measured, and gastric biopsy specimens were taken for gastrin and somatostatin messenger RNA (mRNA) analysis and H. pylori diagnosis. RESULTS: In response to gastrin-releasing peptide, the increase in plasma gastrin concentrations in the infected patients was significantly higher than in the uninfected. Antral gastrin mRNA also increased significantly in the infected group but decreased significantly in the uninfected group. Basal somatostatin was lower in the infected group; gastrin-releasing peptide produced a significant increase in antral somatostatin mRNA concentration in infected, but not uninfected, patients. CONCLUSIONS: The somatostatin cell responds to gastrin-releasing peptide in H. pylori infection. Gastrin-releasing peptide normally inhibits gastrin mRNA expression, but inhibition is deficient in H. pylori infection, possibly because of low stimulated somatostatin levels.
