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

Omeprazole inhibits H+,K+-ATPase, the enzyme responsible for the exchange of H+ and K+ in the final step in the acid secretory process within the parietal cell. It has been shown to produce a marked and long-lasting inhibition of acid secretion with a decrease in 24-hour intragastric acidity after repeated daily dosing. Omeprazole has been shown to give significantly higher healing rates than ranitidine or cimetidine in patients with duodenal ulcer and gastric ulcer. Similarly, a more pronounced effect on ulcer symptoms has been observed. In patients with reflux esophagitis, omeprazole has been shown to decrease the time with an acid milieu in the esophagus. Omeprazole has consistently given about twice as high healing rates and faster decrease in symptoms than with ranitidine. In patients with Zollinger-Ellison syndrome, omeprazole has been found to have a rapid and long-lasting effect on acid secretion and acid-induced symptoms.
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PMID:Clinical utility and safety of omeprazole. 265 79

The substituted benzimidazoles are a new class of drugs with a unique antisecretory action. These agents have great potential for treatment of acid-peptic disease because they produce substantial, long-lasting inhibition of gastric acid secretion by inhibiting gastric H+,K+-ATPase in the gastric parietal cell. Clinical trials of omeprazole, a substituted benzimidazole, indicate that it is safe and effective for short-term treatment of patients with duodenal or gastric ulcer, and it is highly effective for long-term treatment of patients with Zollinger-Ellison syndrome.
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PMID:Treatment of acid-peptic diseases by inhibition of gastric H+,K+-ATPase. 301 Aug 11

The inhibitory effect of omeprazole on acid formation has been studied in vitro in gastric glands and partly purified H+,K+-ATPase, prepared from mucosa obtained either from healthy subjects by gastroscopic biopsy or from gastric ulcer patients during antrectomy. The effect of omeprazole was compared with the inhibitory pattern of the H2-antagonist cimetidine. Acid production in the glands was determined by measuring the accumulation of 14C-aminopyrine. In glands isolated from patients, omeprazole inhibited acid production maximally stimulated by histamine, db-cAMP, and potassium in a dose-dependent manner, with an IC50 value of about 50 nM irrespective of the agonist used. In contrast, cimetidine inhibited only histamine-induced aminopyrine accumulation, with an IC50 of about 30 micron. The inhibitory effect of omeprazole in db-cAMP-stimulated glands from healthy volunteers was of the same magnitude as seen in glands from gastric ulcer patients. Basal aminopyrine accumulation in glands from both patients and healthy volunteers was almost totally inhibited by omeprazole, whereas cimetidine was without effect. Omeprazole also concentration-dependently inhibited the H+,K+-ATPase activity in isolated gastric membrane vesicles. The estimated IC50 value was 4 micron.
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PMID:Inhibitory action of omeprazole on acid formation in gastric glands and on H+,K+-ATPase isolated from human gastric mucosa. 301 68

The pharmacology, pharmacokinetics, clinical efficacy, adverse effects, and dosage and administration of omeprazole are reviewed. Omeprazole, a substituted benzimidazole, has a unique site and mechanism of action because it inhibits the proton pump--i.e., hydrogen, potassium adenosine triphosphatase (H+,K+-ATPase)--and consequently blocks the final common step in the gastric acid secretory pathway. Omeprazole inhibits basal and histamine-, gastrin- and pentagastrin-stimulated gastric hydrochloric acid secretion. It produces a dose-dependent reduction in gastric acidity, gastric acid output, and gastric juice volume and has variable effects on pepsin secretion. Omeprazole has no documented effect on esophageal motility or lower esophageal sphincter pressure. Omeprazole is variably absorbed from the gastrointestinal tract, and food appears to decrease the rate, but not the extent, of drug absorption. The drug is approximately 95% bound to plasma proteins and is metabolized to inactive components that are enterohepatically or renally eliminated. Omeprazole is more effective (in most studies) than H2-receptor antagonists in treating duodenal ulcer, at least as effective in treating benign gastric ulcer, and more effective in treating reflux esophagitis. Omeprazole has been used successfully in patients with Zollinger-Ellison syndrome refractory to treatment with H2-receptor antagonists. Gastrointestinal complaints (nausea and diarrhea) are the most commonly reported adverse effects associated with omeprazole therapy. The most frequently reported laboratory abnormality occurring with omeprazole use is elevation of serum aspartate aminotransferase and alanine aminotransferase concentrations. Omeprazole will serve a valuable role in the management of gastrointestinal tract ulcers and hypersecretory conditions.
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PMID:Therapeutic evaluation of omeprazole. 306 85

Hinesol, a major component of the crude drug "So-jutsu" (Atractylodis Lanceae Rhizoma), strongly inhibited H+,K+-ATPase activity with a IC50 value of 5.8x10(-5) M. It also inhibited Na+,K+-ATPase, Mg2+-ATPase, Ca2+-ATPase, and H+-ATPase activities, although the inhibition rate was lower. No effects on alkaline or acid phosphatase activities were observed. The mechanism by which hinesol inhibited H+,K+-ATPase activity was studied in detail. The inhibition was uncompetitive with respect to ATP, and it increased as the Mg2+ concentration was raised, whereas it was not affected by the K+ concentration. The activity of K+-dependent p-nitrophenyl phosphatase (K+-pNPPase), a partial reaction of H+,K+-ATPase, was inhibited by hinesol noncompetitively with respect to pNPP (IC50 value of 1.6x10(-4) M), and competitively with respect to K+, whereas it was not affected by the Mg2+ concentration. These results suggest that hinesol is a relatively specific inhibitor of H+,K+-ATPase. It appears that hinesol reacts with enzyme in the E1 state in the presence of ATP and Mg2+ and forms the complex hinesol-H+ E1-ATP or hinesol x E1-P, blocking the conformational change to the E2 state. Furthermore, hinesol enhanced the inhibitory effect of omeprazole on H+,K+-ATPase, and the inhibitory site of hinesol was different from that of omeprazole. The effect of So-jutsu as an anti-gastric ulcer agent may be ascribed to the inhibitory effect of hinesol on H+,K+-ATPase activity.
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PMID:Inhibition of H+,K+ -ATPase by hinesol, a major component of So-jutsu, by interaction with enzyme in the E1 state. 1071 47

Anti-ulcer potential and proton pump inhibitory activity of kolaviron (KV) isolated from Garcinia kola Heckel has been evaluated using different ulcer models. Cold-restraint (CRU), aspirin (ASP), alcohol (AL), pyloric ligation (PL) induced gastric ulcer models were used to assess anti-ulcerogenic activity of KV in rats. Effects of KV on gastric juice for free and total acidity, peptic activity and mucin secretion were also evaluated. The H+, K+-ATPase activity was assayed in gastric microsomes, spectrophotometrically. Results of this study showed that KV (200 mg/kg) reduced the incidence of ulcers in CRU (69.0%), PL (67.6%), ASP (68.6%) and AL (51.5%). Reductions were also observed in free acidity (32.6%), total acidity (56.2%) and peptic activity (35.4%) with increase in mucin secretion by 40.1%. KV inhibited the H+,K+-ATPase activity with IC50 of 43.8 microg/ml compared with omeprazole with IC50 of 32.3 microg/ml. KV showed both cytoprotective and anti-secretory potentials against peptic ulcer models, and a proton pump inhibitory activity. KV may emerge as a potent anti-ulcer compound.
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PMID:Anti-ulcerogenic and proton pump (H+, K+ ATPase) inhibitory activity of Kolaviron from Garcinia kola Heckel in rodents. 2170 26