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)

To elucidate the role of arginine vasopressin (AVP) in the development of stress-induced gastric ulcer, the mucosal lesions after restraint and water immersion were examined in Brattleboro strain rats with hereditary hypothalamic diabetes insipidus (DI) and in Long-Evans rats (LE) used as controls. Restrained animals were immersed in water for 2 h, and the size of lesion was expressed as percentage of the lesion area to the total glandular mucosal area, which were defined as ulcer index (UI). In DI rats, UI was significantly higher than in control LE rats, despite the attenuated responses of plasma adrenocorticotropic hormone (ACTH) to stress. Although subcutaneous injection of selective antidiuretic analogue 1-desamino-8-D-AVP did not affect UI, intracerebroventricular (icv) administration of AVP reduced UI in DI rats, and icv administration of V1 antagonist [d(CH2)5Tyr(Me)]AVP elevated UI in LE rats. These results indicate that endogenous AVP plays a role in preventing the formation of gastric ulcers induced by stress via a central V1 receptor. Furthermore, we suggest that elevation of ACTH in plasma is not essential in the development of stress-induced gastric ulcer in rats.
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PMID:Role of endogenous vasopressin in development of gastric ulcer induced by restraint and water immersion. 820 19

The in vitro effect of urea and hydrolysis of urea by urease on mucus H+ permeability is reported here. The effective DHCl values indicate a strong pH dependence for H+ diffusion in both water and mucus layers, with no apparent trend at concentrations between 1 and 50 mM urea. However, the estimated DHCl at near-neutral and alkaline pH are 4- to 10-fold lower through mucus than through aqueous films. Moreover, the pKa values of HCO3- and NH3 (generated by urease action on urea) had a profound effect on measured DHCl. These in vitro studies suggest that a high local concentration of NH3 and HCO3- within the mucus layer, generated by the action of Helicobacter pylori urease on endogenous intragastric urea, could greatly accelerate proton flux to the surface epithelium by operation of a buffer shuttle. This results in enhanced H+ permeability, particularly at pKa values of HCO3- and NH3, and in extreme circumstances it may result in gastric ulcer formation.
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PMID:An in vitro study of enhanced H+ diffusion by urease action on urea. Implications for Helicobacter pylori-associated peptic ulceration. 826 22

Chronic nicotine treatment worsens stomach mucosal damage by cold (4 degrees C) and restraint (stress): it dose- and time-dependently intensifies stress-evoked gastric glandular ulceration, mast cell degranulation and motility. Nicotine 50 micrograms/ml drinking water, given ad libitum to female Sprague-Dawley rats for 10 days, increases the sensitivity of the isolated stomach strip to acetylcholine-induced contractions; atropine abolishes this action. The isolated anococcygeus muscle from nicotine-treated male rats shows increased sensitivity to noradrenaline-induced contractions, but not to those by acetylcholine. Hexamethonium or atropine pretreatment antagonises stress-induced gastric effects in nicotine-drinking rats. Muscarinic M1- and M2-, but not M3-, receptor block (by pirenzepine, AF-DX 116BS and HHSiD, respectively) inhibits stress ulcer formation in female rats. Although tobacco smoking has been reported to increase free radical formation, mucosal xanthine oxidase which initiates free radical formation is uninfluenced by nicotine; antagonising this enzyme (by allopurinol) or hydroxyl free radical scavenging (by dimethylsulfoxide) does not lessen the effect of nicotine on stress-evoked ulceration. The findings suggest that chronic nicotine treatment produces partial ganglionic blockade of the vagal nerve which leads to muscarinic receptor supersensitivity. This phenomenon contributes significantly to the ulcer-worsening mechanism; muscarinic M1- and M2-receptors appear to be involved. The gastric ulcer-aggravating effect of nicotine in stressed rats appears not to be due to increased free radical formation.
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PMID:Nicotine and gastric ulcers in stress. 829 87

To clarify the ability of endoscopic ultrasonography (EUS) to diagnose gastric ulcer, we induced gastric ulcer (19 open ulcers and 11 ulcer scars) by injecting acetic acid into the stomach via an endoscope in 15 dogs. The stomachs were resected and scanned by EUS in a water bath, and the findings were compared with the histologic observations. The ulcer depth was correctly diagnosed in 29 of 30 instances (96.7%). In active, open ulcers the width and depth of the ulcer crater and the thickness of the gastric wall around the crater measured in the photographs obtained by EUS corresponded with those observed in histologic photographs. In the ulcers disrupting the muscularis propria layer the distance between the disrupted muscularis propria layer in EUS also corresponded to the histologic observations. In all ulcer lesions the low-echoic area below the ulcer in EUS corresponded to the histologic area of granulation or fibrosis. However, it was difficult to distinguish granulation from fibrosis by EUS. EUS is thus considered useful for evaluating gastric ulcers quantitatively in the clinical setting.
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PMID:Evaluation of acetic acid-induced gastric ulcers in dogs by endoscopic ultrasonography. 830 7

The in vitro effect of ammonium bicarbonate buffer on mucus H+ permeability is reported here. The diffusional resistance of mucus and water was demonstrated to be dependent on buffer concentration, and the contrast between the two types of layers was most pronounced for low buffer concentration near neutrality. Moreover, the pKa values of HCO3- and NH3 had a profound effect on measured DHCl. These in vitro studies suggest that a potentially damaging high local concentration of NH3 and HCO3- within the mucus layer generated by the action of Helicobacter pylori urease on endogenous intragastric urea could greatly accelerate proton flux to the surface epithelium by operation of a buffer shuttle. This results in enhanced H+ permeability, particularly at pKa values of HCO3- and NH3, and that in extreme circumstances this may result in gastric ulcer formation.
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PMID:Enhanced H+ diffusion by NH4+/HCO3-: implications for Helicobacter-pylori-associated peptic ulceration. 851 85

The anti-ulcer effects of a natural mixture of higher aliphatic primary alcohols, designated D-002, isolated from beeswax, were compared with those of cimetidine on indomethacin-, ethanol-, water-immersion-induced ulcers and on gastric secretion in rats. D-002 (25-50 mg kg-1 p.o.) was similar to cimetidine in dose-dependently reducing the duration of indomethacin-induced ulcers while also being effective in preventing ethanol-induced ulcers, which are not affected by cimetidine. On the other hand, D-002 (100 mg kg-1) moderately decreased the volume of gastric basal secretion in pylorus-ligated rats, but not the acidity. Nevertheless, it inhibited gastric ulcer induced by pylorus-ligation at doses (50 mg kg-1) that were ineffective in decreasing the volume. In addition, 100 mg kg-1 of D-002 prevented the formation of acute gastric ulcers induced in rats by water-immersion stress. The results demonstrate the anti-ulcer activity of the preparation in different experimental models suggesting its potential value for ulcer therapy.
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PMID:Anti-ulcer activity of higher primary alcohols of beeswax. 858 84

Our objectives were to determine whether rebamipide, a unique antiulcer agent, would inhibit adhesive reactions between neutrophils and endothelial cells as well as the production of active oxygen species from neutrophils elicited by an extract of H. pylori. A water extract of H. pylori that was prepared from biopsy materials obtained from a patient with gastric ulcer increased the surface expression of CD18 on human neutrophils isolated from peripheral blood, the adhesion of neutrophil-endothelial cells, and the production of active oxygen species by neutrophils. Rebamipide, at concentrations of 10(-5) and 10(-6) M, reduced the adherence of neutrophils to endothelial cells as well as the CD18 expression on neutrophils induced by this bacterial extract. Rebamipide also inhibited the production of active oxygen species from neutrophils stimulated by H. pylori extract. These results suggest that rebamipide protects against the gastric mucosal inflammation associated with H. pylori by inhibiting neutrophil function.
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PMID:Rebamipide protects against activation of neutrophils by Helicobacter pylori. 865 44

Congenital esophago-bronchial fistula with diverticulum is rare, and in Japan only 29 cases have been reported. A 59-year-old man had suffered from recurrent pulmonary infections and often complained of coughing while drinking water during the previous two years. An UGI series for follow-up of gastric ulcer revealed an esophago-bronchial fistula, located between the mid-esophagus and B10 of the right lung. We resected the diverticulum and the fistulous tract with a partial excision of S10. Histological examination revealed that the squamous epithelium with the muscularis mucosa of the esophagus was smoothly connected to the columnar epithelium of the bronchus. Thus, we diagnosed this fistula as congenital, not acquired. Comparison of the previous UGI series before presenting symptoms with that performed at this admission showed the lengthening and thickening of this congenital fistula during the three-years period. We suspected that the influence of acquired factors may cause a congenital fistula to manifest various clinical symptoms.
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PMID:[A case report--congenital esophago-bronchial fistula with esophageal diverticulum]. 874 54

The experimental Wistar rats were divided into two groups, the acupuncture group and the control group. Stress-induced gastric ulcer models were established by immersion of restrained rats in water. The electroacupuncture was able to protect stress rat from stress induced peptic ulcer. The results indicated that electroacupuncture protecting rat from stress ulceration was relevant to enhancing gastric mucosal barrier, stabilizing gastric mast cell and inhibiting the gastrin levels in gastric mucous.
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PMID:[Effects of electroacupuncture on gastrin, mast cell and gastric mucosal barrier in the course of protecting rat stress peptic ulcer]. 875 29

A 68-year-old man developed severe consciousness disturbance after daily administration of 20 mg omeprazole for four days for the treatment of bleeding gastric ulcer. Systemic investigation revealed severe hyponatremia (111 meq/liter). Consciousness did not become clear until his sodium intake was increased to 480 meq/day, and his serum sodium concentrations reached 130 meq/liter. After the discontinuation of omeprazole, his serum sodium levels returned to the normal range with only minimum supplementation of sodium in the form of dietary sodium chloride intake of 10 g/day. Although the mechanism of hyponatremia induced by omeprazole is not clear, an excessive loss of urinary sodium appears to be more likely than water retention with an increase in fluid intake. The literature was also reviewed.
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PMID:Hyponatremia with consciousness disturbance caused by omeprazole administration. A case report and literature review. 876 88


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