Linked Life Data

8266022

Source:http://linkedlifedata.com/resource/pubmed/id/8266022

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
1994-1-25
pubmed:abstractText
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.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0036-5521
pubmed:author
pubmed:issnType
Print
pubmed:volume
28
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
915-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
An in vitro study of enhanced H+ diffusion by urease action on urea. Implications for Helicobacter pylori-associated peptic ulceration.
pubmed:affiliation
Dept. of Medicine (Clinical Biochemistry), University of Manchester, Hope Hospital, Salford, UK.
pubmed:publicationType
Journal Article, In Vitro