Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01350 (gastrin)
 9,683 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Chronic gastritis is a common inflammatory disease. In a number of patients, the inflamed gastric mucosa shows a gradual tendency to become atrophic (atrophic gastritis). Gastritis tends to be lifelong, and spontaneous healing is rare. With very few exceptions (e.g. in patients with autoimmune chronic corpus gastritis), gastritis is associated with the presence of the bacterium Helicobacter pylori. Inflammation and atrophy of the gastric mucosa result in impairment of gastric secretory functions (e.g. secretion of gastric acid, pepsin and gastrin). Such impairment is dependent on the topographic type of gastritis; i.e. whether the inflammation and atrophy occur in the antrum (chronic antral gastritis), corpus (chronic corpus gastritis) or in both the antrum and corpus simultaneously (chronic pangastritis). Gastritis of different topographic types associates with different gastric diseases. In patients with H. pylori-related antral or pangastritis, peptic ulcer disease, and in particular duodenal ulcer, is common (with an incidence exceeding 20% after 10 years' follow-up), as compared with peptic ulcer disease, which is very rare in patients with a normal stomach. Gastric ulcer may sometimes occur in patients with a rather atrophic stomach, but both gastric and duodenal ulcers are extremely rare in patients in whom the gastritis accompanies severe atrophic changes in the corpus mucosa. Routine biopsies from the antrum and corpus, and interpretation of the results in the light of the data on gastritis and its atrophic sequelae, allow the gastroenterologist to predict the risk and likelihood of peptic ulcer disease in patients with gastritis.
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PMID:Natural history of gastritis and its relationship to peptic ulcer disease. 139 47

Previous studies of gastric secretory function and serum gastrin levels in patients with chronic renal failure (CRF) have yielded conflicting results. In a study of 30 patients on regular hemodialysis, serum gastrin levels were higher than normal (p less than 0.05), and the gastric secretory response to pentagastrin was normal for the group as a whole. There were, however, 8 patients who were hypochlorhydric (4 achlorhydric) and 7 who were hyperchlorhydric. The patients with gastric hyposecretion were older, predominantly male and this group was associated with the highest gastrin levels as well as the highest incidence of gastrointestinal hemorrhage. Chronic gastritis is thus more common in CRF than generally believed and may be responsible for much of the morbidity from gastrointestinal complications during hemodialysis.
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PMID:Gastric acid secretion and serum gastrin levels in patients with chronic renal failure on regular hemodialysis. 735 85

A critical evaluation has been made of the available evidence in man of the effects of prolonged low acid states on the structure and function of the stomach. Various human models have been examined. 1. Ageing does not affect acid output from the normal male stomach, and there may be an increase in women. With progressive atrophy of the corpus mucosa, which is more frequent and rapid in patients with gastric ulcer, there is an associated loss of secretory function. Chronic gastritis and atrophy are the most important age-related changes, which in many cultures are hypothesized to develop via a prior Helicobacter pylori-related gastritis. However, H. pylori colonization of the mucosa decreases with increasing grades of gastric atrophy probably because intestinal metaplasia provides a hostile environment. Atrophy and intestinal metaplasia are associated with precancerous lesions and gastric cancer. Apparent hyperplasia of the gastric argyrophil endocrine cells is a common and spontaneous phenomenon in patients with atrophic gastritis, which in part may be related to the preferential loss of nonendocrine cells. 2. Pernicious anemia is associated with a complete lack of acid production, marked hypergastrinemia, and endocrine cell hyperplasia in the majority of patients. ECL-cell carcinoids and gastric cancer occur with a prevalence of 3-7%, and endoscopic surveillance in routine clinical practice is not warranted. 3. Gastric ECL-cell carcinoids are rare events that have been described in association with two diseases in man, pernicious anemia and Zollinger-Ellison syndrome as part of multiple endocrine neoplasia syndrome type I, and usually relate to marked hypergastrinemia and the presence of chronic atrophic gastritis with gastric antibodies or a genetic defect rather than the presence or absence of acid. Regression or disappearance of ECL-cell carcinoids, either spontaneously or after removal of the gastrin drive, has been recorded. Lymph node, and rarely hepatic, metastases are documented but death in these cases has been anecdotal. 4. Therapy with H2 antagonists may result in up to a twofold rise in serum gastrin levels but in man no endocrine cell hyperplasia has been recorded. However, the data for H2 antagonists on these aspects are very limited. There is no drug-related risk of gastric or esophageal cancer, although the incidence of the latter may be raised. Long-term treatment with omeprazole is associated with a two- to fourfold increase in gastrin levels over baseline values in one third of patients and apparent endocrine cell hyperplasia in 7% of cases overall.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Pathophysiological effects of long-term acid suppression in man. 785 87

Helicobacter pylori is a microaerophilic bacterium initially found in the gastric antrum of patients with peptic ulcer disease. As a result, H. pylori is now believed to have a pathophysiologic role in gastritis as well as in peptic ulcer disease. Several recent studies showed that it may be associated with duodenal ulcer relapse and that eradication therapy using antibiotics may significantly decrease the ulcer recurrence rate in duodenal ulcer patients. Moreover, epidemiological studies suggest that it may increase the relative risk of carcinoma in the stomach and preliminary studies seem to indicate that some low-grade lymphoma in the stomach may regress after H. pylori eradication. Although the mechanisms by which H. pylori induces mucosal injury and/or neoplasm is not clearly understood, several modifications in gastric functions have been reported. The most specific way of detecting H. pylori in tissue is a combination of culture and histologic staining of mucosal biopsy specimens obtained by endoscopy. Rapid urease test, cytology and PCR procedures performed on biopsies may give rapid, sensitive and specific results. Breath test using 13C- or 14C-radiolabelled urea and serology tests are of particular importance when H. pylori diagnosis is needed via no invasive procedures. Helicobacter pylori is supposed to interact with G and D cells. Gastrin and somatostatin are synthetized and released from antral G and gastric D cells respectively. The gastric D cells are in close contact with either G and parietal cells. Gastrin stimulates gastric acid secretion and epithelial gastric cell proliferation (parietal and EC-L cells) while somatostatin inhibits these effects. Chronic gastritis is associated with fundic duodenal ulcer disease. In this situation, basal gastrin and meal- or bombesin-stimulated gastrin in the serum (especially gastrin G17) have been found to be higher in H. pylori positive than in negative patients. Moreover, gastrin decreases up to normal levels after eradication of H. pylori. The long term effect of a such hypergastrinemia is not so far established. The mechanism underlaying hormonal modification is poorly understood. Since no G/D cell ratio modification could be found after H. pylori eradication while the amount of somatostatin increases, one would suggest functional alteration of either G or D cells in the H. pylori-related chronic gastritis. The role of inflammatory mediators on the gastrin release and the processing of progastrin induced by the bacterium need further investigations.
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PMID:[Helicobacter pylori, a rediscovered bacterium. Implication in gastroduodenal diseases]. 789 50

Functional dyspepsia is the most common reason for patients to experience chronic epigastric pain or discomfort. The causes of functional dyspepsia are multifactorial but Helicobacter pylori infection is one likely candidate. Infection with this bacterial pathogen clearly results in chronic mucosal inflammation in the stomach and duodenum, which, in turn, might lead to abnormalities in gastroduodenal motility and sensitivity. Chronic gastritis might also affect a variety of endocrine functions of the stomach including the production of the gastrointestinal hormones and neurotransmitters somatostatin, gastrin and ghrelin. Although these abnormalities might generate symptoms in some patients with functional dyspepsia, the clinical evidence needs to be critically evaluated before this hypothesis can be confirmed. A Cochrane review reported that eradication of H. pylori in these patients had a small but statistically significant long-term effect on symptom relief when compared with placebo, lasting at least 12 months after 1 week of eradication therapy. The efficacy of eradication therapy was seen in all symptom subtypes of functional dyspepsia, but was more marked in Asian than Western patients. This evidence has led to alterations in most of the major guidelines throughout the world, which now recommend H. pylori eradication in patients with functional dyspepsia if they test positive for this bacterium.
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PMID:Helicobacter pylori infection in functional dyspepsia. 2335 94