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)

Patients with late-onset hypogammaglobulinaemia have a very high risk of developing gastric cancer. In such patients there is a high frequency of atrophy of the gastric mucosa. This is reflected in low gastrin content of the antral mucosa, low serum pepsinogen A level and pepsinogen A/C ratio, and reduced serum gastrin secretion in response to bombesin stimulation. There is no evidence to support a role of Helicobacter pylori infection in the aetiopathology of these gastric abnormalities, although prior infection cannot be excluded with certainty. Since patients with early-onset hypogammaglobulinaemia and X-linked agammaglobulinaemia do not show this increased frequency of gastric abnormalities, it is unlikely that the immunoglobulin deficiency per se is responsible for the development of the gastric abnormalities found in patients with late-onset hypogammaglobulinaemia. Because of the very high risk of gastric cancer, regular endoscopic screening is warranted in patients with late-onset hypogammaglobulinaemia.
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PMID:Gastric abnormalities in humoral immune deficiency syndromes. 129 45

Hypersecretion of gastric acid, gastrin, and pepsinogen are considered to be causally related to duodenal ulcer diathesis. Until recently, these abnormalities have been considered to be primary and largely genetically determined. However, Helicobacter pylori infection has been shown to be responsible for several of the abnormalities of gastric secretion in duodenal ulcer. H. pylori infection is not only associated with chronic active inflammation but also with a reduction of somatostatin producing D-cells and somatostatin concentrations in the gastric mucosa. The reduced inhibitory action of somatostatin on the secretion of gastric acid, gastrin, and pepsinogen may be responsible for the hypersecretory state of the stomach in duodenal ulcer. These recent findings have drastically changed our understanding of the pathogenesis of duodenal ulcer.
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PMID:Gastric secretory abnormalities in duodenal ulcer: primary or secondary to Helicobacter pylori infection? 129 57

Recent studies have been reviewed to establish the possible importance of the interaction between Helicobacter pylori infection and gastric acid secretion. H. pylori infection results in increased gastrin release, but this does not lead to gastric acid hypersecretion and gastrin normalizes after eradication of the infection. An optimal, well-tolerated treatment strategy against H. pylori infection has not yet been clearly defined. One potentially useful approach may be to improve the antibacterial efficacy of antibiotics by effectively regulating gastric acidity. H2-receptor antagonists have no effect against H. pylori infection, while omeprazole (an acid pump inhibitor) appears to have a bacteriostatic action. Combination therapy with omeprazole and amoxycillin has been found to eradicate H. pylori in 50-80% of patients with duodenal ulcer, leading to a significant reduction in ulcer recurrence.
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PMID:Helicobacter pylori, peptic ulcer disease and inhibition of gastric acid secretion. 139 40

We have investigated the possibility that hypergastrinaemia in chronic Helicobacter pylori infection is a compensatory response to reduced parietal cell sensitivity to gastrin. The acid response to 45-min infusions of pentagastrin at sequential doses (micrograms/kg/h) of 0, 0.031, 0.062, 0.124, and 0.6 was compared before and 1 month after eradication of H. pylori in eight duodenal ulcer patients. The median acid outputs (mmol/h) with the respective infusions were 5.0, 7.5, 26.5, 30.8, and 37.0 when H. pylori-positive and similar at 4.5, 7.1, 22.7, 28, and 31.5 when H. pylori-negative. The median estimated dose of pentagastrin required to produce 50% maximal response (D50) was similar before (0.060 micrograms/kg/h) and after (0.057 micrograms/kg/h) eradication of H. pylori. The median estimated maximal response to pentagastrin (mmol/h) was also similar before (39.2) and after (32.3) treatment. The median basal gastrin concentration was 48 ng/l (range, 22-77) before treatment and fell to 33 ng/l (range, 8-37) after eradication of H. pylori (p = 0.03). These findings show that the parietal cell sensitivity to pentagastrin is unaffected by chronic H. pylori infection in duodenal ulcer subjects and that the hypergastrinaemia cannot be attributed to the bacterium inhibiting parietal cell function.
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PMID:Effect of Helicobacter pylori on parietal cell sensitivity to pentagastrin in duodenal ulcer subjects. 143 39

Patients with duodenal ulcers and Helicobacter pylori infection have elevated plasma gastrin concentrations which fall after suppression of the organism. This may be due to H. pylori elevating the pH of the antral mucous layer, therefore preventing luminal acid from inhibiting gastrin release. To test this idea, we measured the plasma gastrin concentrations under basal conditions and in response to 4% peptone when the gastric lumen was maintained at pH 2.5 and at pH 5.5 by gastric perfusion. We studied 11 duodenal ulcer patients before and after suppression of H. pylori. Gastrin concentrations were significantly higher before suppression of H. pylori than after treatment in all three states; basal gastrin (pmol/l) fell from 9.2 (3.7-23, median and range) to 5.1 (1.7-15) after treatment; from 11.3 (3.8-29) to 5.9 (5.7-6.1) at pH 2.5 and from 15.2 (3.9-32) to 7.15 (6.1-14) at pH 5.5. The ratio of peptone-stimulated gastrin at pH 2.5/pH 5.5 was similar before (0.8; 0.5-1.7) and after (0.8; 0.5-1.1) suppression of H. pylori. These results indicate that infection with H. pylori increases basal and peptone-stimulated plasma gastrin concentrations, and that this response is independent of luminal pH.
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PMID:pH-dependent secretion of gastrin in duodenal ulcer disease: effect of suppressing Helicobacter pylori. 145 51

The rise in serum gastrin and pepsinogen I after 5 days' treatment with the proton pump inhibitor pantoprazole (40 mg/day) was examined in eight duodenal ulcer patients with Helicobacter pylori infection and compared with eight in whom it had been eradicated. Before treatment, the post-prandial serum gastrin concentrations were higher in the H. pylori-positive than -eradicated patients (p less than 0.05). The median rise in pre-prandial serum gastrin concentrations on treatment was similar in the H. pylori-positive (41%) and -eradicated patients (45%). The rise in post-prandial serum gastrin was also similar in the H. pylori-positive (81%) and -eradicated patients (69%), resulting in significantly higher gastrin concentrations during treatment in the former. The median rise in serum pepsinogen I on treatment was greater in the H. pylori-positive (114%) than in the -eradicated patients (8%), resulting in significantly higher concentrations during treatment in the former. These observations indicate that eradication of H. pylori may be a means of moderating the hypergastrinaemia caused by acid-inhibitory therapy. They also indicate that H. pylori-related hypergastrinaemia is not due to an increase of the antral surface pH by the bacterium's urease activity.
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PMID:Helicobacter pylori and hypergastrinaemia during proton pump inhibitor therapy. 153 64

Twelve patients with active duodenal ulcer disease and Helicobacter pylori infection were treated with 1 g sucralfate q.d.s. for 1 month. Ulcers healed in 8 of the 12 patients without an alteration in the H. pylori-associated antral gastritis. Sucralfate produced a significant fall in basal acid output in all the patients, from a median of 4.8 (range 2.1-12.1) to 1.6 (0.4-8) mmol/h, P less than 0.01, whereas peak acid output was unchanged from 41 (21-59) before to 38 (24-55) mmol/h after treatment. Basal plasma gastrin concentrations and the meal-stimulated integrated gastrin response were not altered significantly by sucralfate: 8 (2-17) pmol/L and 732 (188-1045) pmol. min/L pre-treatment and 6 (2-17) pmol/L and 600 (140-1302) pmol. min/L post-treatment, respectively. The fall in basal acid output observed may contribute to prolonged duodenal ulcer remission after treatment with sucralfate.
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PMID:Sucralfate diminishes basal acid output without affecting gastrin, H. pylori or gastritis in duodenal ulcer patients. 160 44

Duodenal ulcer patients have increased serum pepsinogen I (PGI) concentrations and an increased prevalence of Helicobacter pylori infection. We have examined the effect of eradicating the infection on PGI. In 12 duodenal ulcer patients in whom H. pylori was successfully eradicated, the median basal PGI was 90 ng/ml (range, 37-252) before treatment and fell to 74 ng/ml (28-197) 1 month after treatment (p less than 0.01). In 12 patients in whom therapy failed to eradicate the infection, the PGI was 87 ng/ml (35-128) before treatment and remained unchanged at 83 ng/ml (36-119) 1 month after treatment. In the group with successful eradication the median basal plasma gastrin was 43 ng/l (15-95) before treatment and fell to 30 ng/l (17-75) 1 month after treatment (p less than 0.003), but there was no change in the corresponding values in the group without eradication (55 ng/l; range, 25-120, and 45 ng/l; range, 5-175; p = 0.9). In conclusion, eradication of H. pylori results in a fall in PGI and plasma gastrin, and these changes are not due merely to the anti-H. pylori drugs themselves or to discontinuation of previous ulcer therapy.
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PMID:Effect of Helicobacter pylori on serum pepsinogen I and plasma gastrin in duodenal ulcer patients. 173 37

The mechanism of the hypergastrinaemia associated with Helicobacter pylori infection is unknown. It may be an effect of the ammonia produced by the bacterium near the antral epithelial surface. We have examined the effect on serum gastrin of inhibiting H pylori urease activity with acetohydroxamic acid in six duodenal ulcer patients. On day 1 the fasted patients received placebo tablets at 8 am, a peptide meal at 10 am, and a 14C urea breath test at 11.30 am. The next day 750 mg acetohydroxamic acid was administered orally in place of the placebo. The median (range) 30 minute breath test value (dose/mmol CO2 X kg body wt X 100) was 152 (111-335) on day 1, but only 22 (14-95) the next day (p less than 0.03). Further studies performed in one subject confirmed that acetohydroxamic acid lowered the ammonium concentration and raised the urea concentration in gastric juice. The inhibition of urease activity and ammonia production did not result in a fall in the basal gastrin concentration or in the median integrated gastrin response to the peptide meal, which was 78 ng/1.h (range 21-222) on day 1 and 79 ng/1.h (33-207) the next day. Ten days after acetohydroxamic acid, the urea breath test values were similar to those before treatment. This study shows that the raised gastrin concentration in patients with H pylori infection is not directly related to the organism's urease activity. It also shows that temporary suppression of H pylori urease activity does not clear the infection.
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PMID:Effect of inhibition of Helicobacter pylori urease activity by acetohydroxamic acid on serum gastrin in duodenal ulcer subjects. 188 67

The role of Helicobacter pylori infection in causing chronic dyspepsia is in need of further clarification. More well-designed prospective studies are necessary to ascertain whether and to what extent H. pylori-related chronic inflammation in the stomach and the duodenum causes dyspeptic symptoms; whether and to what extent there is a symptom cluster characteristic for H. pylori-related gastroduodenitis; whether and to what extent H. pylori infection is demonstrable in the chronic dyspeptic population; and whether and to what extent H. pylori infection interferes with gastrin homoeostasis and acid secretion or induces motor disturbances. Well-designed prospective H. pylori-eradication studies may further contribute in unravelling its role in chronic dyspepsia, especially in patients with active polymorphonuclear gastroduodenitis and hyperacidity.
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PMID:Is gastroduodenitis a cause of chronic dyspepsia? 189 28


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