Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038358 (gastric ulcer)
 5,179 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We assessed the intraluminal pH and mucosal prostaglandin E2 (PGE2) concentrations in patients (nonresponders) whose gastric ulcer did not heal after an initial 2 months and subsequent 3 months of treatment with one of five H2-receptor antagonists (H2RAs). The efficacy of misoprostol, a PGE1 analogue, or AG-1749, a proton-pump inhibitor, on ulcer healing in nonresponders was also tested. The percentage of time (24-h measurement) during which the pH was 3 or more was higher in the basal condition (no H2RA) in nonresponders than in good responders with healing in the first 2 months. H2RAs increased this percentage satisfactorily in nonresponders as well as in good responders. The mean mucosal PGE2 concentration in the ulcer rim was 26 ng/g of tissue in nonresponders, much lower than in good responders. Treatment with misoprostol combined with an H2RA resulted in 60% success for ulcer healing within the next 2 months in nonresponders, without affecting the intraluminal pH measured during treatment with an H2RA alone. AG-1749 raised the percentage of time with high pH to 99% from the 68% obtained with an H2RA and cured 88% of this type of ulcer. These results suggest that extremely low PGE2 levels in gastric mucosa are related to the effectiveness of the H2RA. In such a condition, the small amount of gastric acid that is still secreted even during treatment with an H2RA may interrupt ulcer healing. Therefore, treatment with a prostaglandin analogue combined with an H2RA or treatment with a proton-pump inhibitor may be useful for ulcer healing in nonresponders.
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PMID:H2-receptor antagonist-refractory ulcer: its pathophysiology and treatment. 168 56

To find out whether non-steroidial anti-inflammatory drugs (NSAIDs) inhibit the proliferation of mucosal cells that normally leads to healing of gastric ulcers a microdissection technique was used to quantify mitosis in gastric glands at the ulcer edge in relation to that in the adjacent mucosa. The regeneration index thus obtained of the ulcer edge was greater in the 9 subjects with gastric ulcers not taking NSAIDs (mean index 3.1 [SEM 0.61]) than that in the 8 patients taking NSAIDs (index 1.49 [0.16]). In rats in which gastric ulcers were produced with a cryoprobe, the ulcers were larger and slower to heal in those receiving indomethacin than in controls; also, immunohistochemical staining indicated significantly fewer mitotic cells in glands adjacent to the ulcer in indomethacin-treated rats (8 mitoses [SEM 3]) than in control animals (25 [5]). The prostaglandin E1 analogue misoprostol reversed the inhibition of healing and substantially restored the proliferative rate in the animals. Inhibition of epithelial cell division normally involved in gastric ulcer healing would contribute to the high prevalence of gastric ulcer during NSAID therapy.
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PMID:Inhibitory effect of non-steroidal anti-inflammatory drugs on mucosal cell proliferation associated with gastric ulcer healing. 197 50

Prostaglandin analogues, used in the treatment of duodenal and benign gastric ulcer and in the prevention of gastric ulceration caused by non-steroidal anti-inflammatory drugs, are frequently associated with gastrointestinal side effects, particularly diarrhoea and abdominal cramps. We investigated the effects of misoprostol, a prostaglandin E1 derivative, on bowel motility and faecal loss of fat, water and bile acids in relation to its postprandial vs. preprandial administration. Twelve healthy subjects participated in a double-blind crossover study comparing three 5-day courses of therapy with a washout period of 1-2 weeks between courses. Following a Latin Square design, the dosing regimens were (a) 400 micrograms misoprostol b.d. after meals and placebo b.d. before meals; (b) 400 micrograms misoprostol b.d. before meals and placebo b.d. after meals; (c) placebo before and after meals. Orocaecal transit time measured by H2 breath tests following lactulose administration, was shortest during pre-prandial dosing but was also significantly decreased during post-prandial dosing. The overall treatment difference was highly significant (P less than 0.001), and the difference between each pair of treatments was also statistically significant. Whole bowel transit time studied by means of 3H-PEG 4000 determination in stools, was shorter for the two misoprostol regimens but statistical significance was borderline. The number of stools passed per day was similar in the three groups. During both misoprostol dosing periods, stools were less formed and their content of water, fat and bile acids was higher. There was also more urgency, flatulence, abdominal pain and nausea. It is concluded that the gastrointestinal side effects caused by misoprostol are mainly based on an increased orocaecal transit time. The effects are more important when the drug is administered before meals than after meals.
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PMID:Effects on bowel motility of misoprostol administered before and after meals. 179 84

Synthetic prostaglandins of the E series have cytoprotective and gastric antisecretory actions. Both actions are relevant to their therapeutic usefulness in treating and preventing gastrointestinal mucosal diseases. Controlled clinical studies have shown prostaglandins to be effective treatment for gastric and duodenal ulcer disease. Although used widely in dozens of foreign countries, however, prostaglandins have not been approved by the United States Food and Drug Administration for use in the treatment of peptic ulcer disease. The use of nonsteroidal anti-inflammatory drugs (NSAIDs) is associated with an increased incidence of gastric and duodenal ulcers, gastrointestinal bleeding, and increased morbidity and mortality. Misoprostol, a prostaglandin E1 analogue, is effective in preventing and treating NSAID-induced mucosal damage and has been approved by the Food and Drug Administration for the prevention of NSAID-associated gastric ulcers. Controlled studies have not provided convincing evidence that H2-receptor antagonists or sucralfate prevents NSAID-induced gastric ulcer. Preliminary clinical studies indicate that some E-prostaglandins may also be effective in treating and/or preventing stress ulcer, cystic fibrosis, and hepatorenal syndrome and in improving graft survival in renal transplant patients receiving cyclosporine. Additionally, in vitro and animal studies suggest that prostaglandins may have therapeutic value in inflammatory bowel disease, and they may promote cartilage repair by an inhibitory action on interleukin-1. The latter finding could be of major relevance in preventing cartilage destruction in rheumatic patients. Significant side effects associated with the clinical use of prostaglandins include mild to moderate diarrhea and stimulation of uterine contraction during early pregnancy. Prostaglandins are effective for the treatment of peptic ulcer disease and, to date, are the only effective therapy for preventing the total spectrum of NSAID-induced mucosal damage. These compounds may also prove effective in treating various inflammatory disorders.
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PMID:Prostaglandins: an overview of the worldwide clinical experience. 181 16

A multicenter, double-blind, placebo-controlled trial was undertaken to evaluate the efficacy of the synthetic prostaglandin E1 analog misoprostol in preventing and healing gastric ulcer induced by nonsteroidal antiinflammatory drugs (NSAID) in patients receiving chronic NSAID therapy for osteoarthritis (OA). A total of 420 patients with OA and NSAID-associated abdominal pain who were receiving ibuprofen, piroxicam or naproxen were enrolled in the study. Endoscopy was performed at study entry and after 1, 2 and 3 months of continuous therapy with misoprostol 100 micrograms, misoprostol 200 micrograms or placebo given q.i.d. while NSAID therapy was continued. Treatment failure was defined as development of gastric ulcer (greater than 0.3 cm in diameter). The occurrence of ulcer in each misoprostol group (5.6% and 1.4% for 100 micrograms and 200 micrograms, respectively) was significantly lower (p less than 0.001) than that in the placebo group (21.7%). The statistically significant difference persisted when comparisons were restricted to development of ulcer greater than 0.5 cm in diameter (12.3, 4.2 and 0.7% for placebo, misoprostol 100 micrograms q.i.d. and misoprostol 200 micrograms q.i.d., respectively). Mild-to-moderate, self-limiting diarrhea was the most frequently reported adverse event attributed to misoprostol use.
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PMID:Misoprostol in the prevention of NSAID-induced gastric ulcer: a multicenter, double-blind, placebo-controlled trial. 210 73

Prostaglandins have been shown to prevent the damage to the gastric and intestinal mucosa which has been induced by diverse necrotizing substances. These damaging stimuli increase the liberation of histamine from mast cells. Because of its well known effects on cellular permeability, histamine may serve the initial stimulus for mediating cellular damage. The aim of our study was to investigate the effect of misoprostol, a synthetic PGE1 analog, on tissue histamine concentration and mast cell counts after damage to the gastric mucosa induced by stress, histamine, aspirin and concentrated ethanol in guinea pigs. Misoprostol or its matching placebo were administered intragastrically 3 minutes prior to the ulcerogenic stimulus. After the induction of the injury, the animals were sacrificed, stomachs were examined for ulceration. Gastric and duodenal histamine concentrations were determined. Mast cells from these organs were stained and counted. All four ulcerogenic stimuli resulted in significant gastric ulcer formation. This ulcerogenic action was accompanied by a significant decrease in mucosal histamine concentration and mast cell counts. Misoprostol induced a dose-dependent inhibition of gastric damage, histamine depletion and mast cell destruction. These results indicate that the stabilization of mast cells by misoprostol is an important mechanism for its mucosal protective effects against ulcerogens.
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PMID:Misoprostol prevents damage to the gastric mucosa by stabilizing the mast cells. 244 10

The new prostaglandin E1 analogue, rioprostil, significantly accelerates healing and the elimination of pain in cases of peptic ulcer. The anti-ulcerous potency of this prostaglandin is equivalent to that of cimetidine. In comparison with ranitidine, there is a positive trend in favour of the H2-receptor antagonist, ranitidine, which has a more pronounced antisecretory effect than rioprostil. The differences in the healing rates during treatment with rioprostil and ranitidine are statistically significant in some cases, whereas those relating to pain alleviation are not. In contrast, the therapeutic efficacy of the two substances is almost identical in cases of Ulcus ventriculi. Rioprostil can be used with much the same success as ranitidine for preventing the recurrence of duodenal ulcers. The frequency of diarrhoea during rioprostil treatment, 300 micrograms b.d. and 600 micrograms nocte, is approximately 10%. In only about 1% of the patients does the rioprostil treatment have to be discontinued because of this adverse reaction.
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PMID:Rioprostil in the acute and long-term treatment of peptic ulcers: a review. 251 Feb 69

Both misoprostol (synthetic PGE1 analog) and De-Nol (factor releasing endogenous prostaglandins in the gastric mucosa) can be useful in the treatment of patients with gastric ulcer resistant to cimetidine according to their gastroprotective properties. 64 patients whose gastric ulcer had not healed after 6 weeks of therapy with cimetidine in daily dose of 1000 mg were treated in a comparative short-term trial to assess the relative efficacy of misoprostol (Cytotec; Searle) in daily dose of 800 micrograms (I group; n = 32) and colloidal bismuth subcitrate (De-Nol; Gist-Brocades), four times a day in dose of 5 ml diluted with 15 ml of water (II group; n = 32). Both groups of patients were comparable according to age, sex, duration of ulcer disease, smoking habits, gastric acid secretion, ulcer size and localization in the stomach. The ulcer healing was controlled endoscopically after 2 and 4 weeks of the treatment. Healing rates after 2 weeks of therapy appeared to be 47% for misoprostol and 34% for De-Nol. After 4 weeks of therapy the healing rates were 72% with misoprostol and 63% with De-Nol. No statistically significant differences in the therapeutic efficacy were observed between two groups of the patients. No correlation was found between the ulcer healing rates and size of ulcer, its localization or smoking habits. The moderate side effects (transient diarrhea) were observed in 22% of patients treated with misoprostol. These findings suggest that misoprostol is as effective as De-Nol in the treatment of gastric ulcers resistant to cimetidine.
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PMID:[Misoprostol and de-nol in the treatment of patients with cimetidine-resistant stomach ulcer]. 251 27

Gastrin, a polypeptide hormone secreted by G (gastrin)-cells in the antroduodenal mucosa, is not only a potent stimulant of gastric acid secretion but also exerts trophic actions on the parietal, chief and enterochromaffin-like cells in the oxyntic mucosa. Gastrin plays a crucial role in the pathogenesis of hypergastrinaemic peptic ulcer disease, i.e. in the Zollinger-Ellison syndrome, antral G-cell hyperfunction and retained excluded antrum after subtotal gastrectomy. In patients with normogastrinaemic duodenal ulcer disease the feedback mechanism between gastric acid and gastrin secretion is impaired, while in gastric ulcer patients gastrin secretion is appropriately regulated by gastric acid. Antisecretory drugs may exert varying effects on gastrin secretion. Potent antisecretory drugs, such as omeprazole, increase serum and antral gastrin concentrations, whereas histamine H2-receptor antagonists, such as cimetidine, ranitidine, famotidine and roxatidine, have little influence on gastrin. Interestingly, antisecretory doses of prostaglandin E2-analogues, such as enprostil and arbaprostil [15(R)-15-methylprostaglandin E2], inhibit gastrin secretion, while gastrin is not influenced by prostaglandin E1-analogues, e.g. misoprostol. Somatostatin and the somatostatin-analogue SMS 201-995 reduce serum gastrin levels and gastric acid secretion.
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PMID:The significance of gastrin in the pathogenesis and therapy of peptic ulcer disease. 306 68

Misoprostol is an E1 prostaglandin analog. Most of the other synthetic prostaglandins that are being studied in advanced clinical trials for gastrointestinal diseases are E2 derivatives. Misoprostol has shown a dose-related antisecretory effect that lasted 3-5.5 hr. In addition, animal studies have shown cytoprotective properties that are being confirmed in clinical studies. Ulcer-healing trials using four times daily dosing appear to parallel the antisecretory dose-response curve up to a dose of 200 micrograms qid. Evidence presented in this supplement suggests a further increase in healing-rate response at 300 micrograms misoprostol qid. The misoprostol healing rates obtained in duodenal ulcer and gastric ulcer therapy at 200 micrograms qid are not significantly different from those seen in the same studies with cimetidine at a dose of 300 mg qid. No significant rebound in recurrence has been observed during follow-up for 12 months after short-term 100- and 200-micrograms qid misoprostol treatment. The most frequent adverse effects are dose-related diarrhea and abdominal cramping, which are transient in most patients and have not caused a significant problem in clinical use. There is also a tropic effect on the pregnant uterus, which was observed in a special pharmacologic clinical study. No significant abnormalities have been detected in clinical laboratory tests or gastric biopsies. There have also been no adverse effects noted on blood pressure, pulse, platelets, the immune system, pulmonary function, gastrointestinal hormones, or the endocrine system. These previously discussed characteristics of misoprostol, and current data, suggest that this prostaglandin E1 derivative may be an important addition to the treatment of peptic ulcer disease.
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PMID:Overview of misoprostol clinical experience. 308 Feb 88


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