| Enhanced H+ diffusion by NH4+/HCO3-: implications for Helicobacter-pylori-associated peptic ulceration. | |
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MedLine Citation:
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PMID: 8513985 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
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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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Authors:
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M A Desai; P M Vadgama |
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Publication Detail:
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Type: In Vitro; Journal Article |
Journal Detail:
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Title: Digestion Volume: 54 ISSN: 0012-2823 ISO Abbreviation: Digestion Publication Date: 1993 |
Date Detail:
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Created Date: 1993-07-22 Completed Date: 1993-07-22 Revised Date: 2006-11-15 |
Medline Journal Info:
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Nlm Unique ID: 0150472 Medline TA: Digestion Country: SWITZERLAND |
Other Details:
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Languages: eng Pagination: 32-9 Citation Subset: IM |
Affiliation:
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Department of Medicine (Clinical Biochemistry), University of Manchester, Hope Hospital, Salford, UK. |
Export Citation:
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APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
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Animals Bicarbonates / pharmacology* Gastric Mucosa / drug effects*, metabolism Helicobacter Infections / complications* Helicobacter pylori / enzymology* Hydrogen-Ion Concentration Mucus / drug effects* Stomach Ulcer / microbiology* Swine Urease / metabolism* |
| Chemical | |
Reg. No./Substance:
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0/Bicarbonates; 1066-33-7/ammonium bicarbonate; EC 3.5.1.5/Urease |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
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