https://www.thelancet.com/pdfs/journals/lancet/PIIS0140-6736(09)60938-7.pdf

Peptic ulcer disease

Background Misoprostol is effective for ulcers associated with the use of nonsteroidal antiinflammatory drugs (NSAIDs) but is often poorly tolerated because of diarrhea and abdominal pain. We compared the efficacy of omeprazole and misoprostol in healing and preventing ulcers associated with NSAIDs. Methods In a double-blind study, we randomly assigned 935 patients who required continuous NSAID therapy and who had ulcers or more than 10 erosions in the stomach or duodenum (or both) to receive 20 mg or 40 mg of omeprazole orally in the morning or 200 μg of misoprostol orally four times daily. Patients were treated for four weeks or, in the absence of healing, eight weeks. Treatment success was defined as the absence of ulcers and the presence of fewer than five erosions at each site and not more than mild dyspepsia. We then randomly reassigned 732 patients in whom treatment was successful to maintenance therapy with 20 mg of omeprazole daily, 200 μg of misoprostol twice daily, or placebo for six months. Re...

/pdf/omeprazole-compared-with-misoprostol-for-ulcers-associated-4bsqja1hck.pdf

Omeprazole Compared with Misoprostol for Ulcers Associated with Nonsteroidal Antiinflammatory Drugs

Campylobacter pyloridis is a spiral bacterium which was seen by histopathologists several years before it was cultured in 1982 in Perth, Western Australia. It has unique cellular fatty acids, predominantly tetradecanoic acid and cis-11, 12 methylene octadecanoic acid. It also has a unique ultrastructure which is different from that of other campylobacters. C pyloridis possesses a powerful urease enzyme and produces large amounts of extracellular catalase. Both these features may be important virulence factors, allowing it to occupy a protected niche in the stomach below the mucus layer but above the gastric mucosa. Specific lesions are found in the gastric mucosa, and ultrastructural studies show the presence of adherence pedestals identical with those found with enteropathogenic Escherichia coli of the intestine. Histological examination of gastric biopsy tissue has shown that C pyloridis is strongly associated with active chronic gastritis, when polymorphonuclear leucocytes are present, and is not found on normal mucosa except when a biopsy specimen from elsewhere in the stomach shows active chronic gastritis. When patients with symptoms caused by gastritis are identified dual antibacterial treatment, combining the action of bismuth in the stomach with a systemic antibiotic, can eradicate C pyloridis, with remission of symptoms and restoration of normal epithelial morphology. Most peptic ulcers relapse after modern acid reducing treatment, and antibacterial treatment may be beneficial in preventing relapse.

https://jcp.bmj.com/content/jclinpath/39/4/353.full.pdf

Campylobacter pyloridis, gastritis, and peptic ulceration.

Surface active drugs: self-association and interaction with membranes and surfactants. Physicochemical and biological aspects

The ability of an epithelium to prevent permeation of noxious agents has not been well studied except in the gastrointestinal tract where exclusion of H+ has clinical significance. This article reviews the permeation routes across epithelia both as elucidated in the extensive electrophysiological work done in recent years and as demonstrated in morphological studies. We thus place concepts about gastrointestinal barrier function into the framework of transport physiology. Both the permeability and permselectivity of epithelial barriers are reviewed here. The effects of physical agents (pressure and electric current), polyvalent cations, organic compounds with both specific (channel blocking) and nonspecific (detergent) membrane properties, cyclic nucleotides, microfilament-active agents, and particularly H+ on both the barrier function (permeability and permselectivity) and transport function of epithelia are considered. Based on the available data, an important role for active Na+ transport in the maintenance of the epithelial barrier function can be postulated.

https://www.physiology.org/doi/pdf/10.1152/ajpgi.1981.241.4.G275

Barrier function of epithelia

Destruction of the Gastric Mucosal Barrier by Detergents and Urea

Gastric Mucosal Injury by Fatty and Acetylsalicylic Acids

Functional significance of gastric mucosal barrier to sodium.

SummaryThe effect of ethanol upon the barrier function of the stomach was studied by irrigating pouches of the canine oxyntic glandular mucosa with solutions of ethanol ranging from 0.5 to 27% w/v. Solutions of 8% or less did not damage the mucosal barrier as judged by the fluxes of Na+, K+ and H+. Solutions of 14 and 27% broke the barrier, for fluxes of the ions across the mucosa were greatly increased during and following ethanol application. In contrast to acetylsalicylic acid which is much more damaging in acid than in neutral solution, ethanol has essentially the same effect upon the barrier when applied in 100 mM HCl or in 30 mM phosphate buffer, pH 7.5. The rate of absorption of ethanol is a linear function of its concentration. The damaging effect of ethanol depends upon the concentration in contact with the mucosa and not upon the quantity absorbed. Low concentrations of ethanol (8% or less) stimulate acid secretion. Histamine could not be detected in the arterial or gastric venous blood of anest...

Ethanol Damage to Canine Oxyntic Glandular Mucosa.

https://www.gastrojournal.org/article/S0016-5085(66)80027-6/pdf

Horace W. Davenport

Papers

Destruction of the Gastric Mucosal Barrier by Detergents and Urea

Gastric Mucosal Injury by Fatty and Acetylsalicylic Acids

Functional significance of gastric mucosal barrier to sodium.

Ethanol Damage to Canine Oxyntic Glandular Mucosa.

Fluid produced by the gastric mucosa during damage by acetic and salicylic acids