Linked Life Data

19000657

Source:http://linkedlifedata.com/resource/pubmed/id/19000657

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2008-12-8
pubmed:abstractText
In distal colon, the limiting factor for Na(+) absorption is represented by the epithelial sodium channel (ENaC). During absorption, high transepithelial Na(+) gradients are observed. In human colon and in HT-29/B6-GR cells, we investigated whether Na(+) back-leakage is prevented by paracellular sealing. Tissues and cells were incubated with corticosteroids. Barrier properties were analyzed in electrophysiological experiments. Subsequently, analysis of ENaC and tight junction protein expression, localization, and regulation was performed. In colon, nanomolar aldosterone induced sodium absorption via ENaC. Concomitantly, paracellular (22)Na(+) permeability was reduced by half and claudin-8 within the tight junction complex was nearly doubled. Real-time PCR validated an increase of claudin-8 transcripts. Two-path impedance spectroscopy following ENaC induction in HT-29/B6-GR revealed a specific increase of paracellular resistance. These results represent an important physiological implication: Na(+) absorption is paralleled by claudin-8-mediated sealing of the paracellular barrier to prevent Na(+) back-leakage, supporting steep Na(+) gradients in distal colon.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
1090-2104
pubmed:author
pubmed:issnType
Electronic
pubmed:day
2
pubmed:volume
378
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
45-50
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Na+ absorption defends from paracellular back-leakage by claudin-8 upregulation.
pubmed:affiliation
Institute of Clinical Physiology, Charité, Campus Benjamin Franklin, Hindenburgdamm 30, 12200 Berlin, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't