Linked Life Data

11399645

Source:http://linkedlifedata.com/resource/pubmed/id/11399645

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2001-6-11
pubmed:abstractText
The purpose of this study was to examine cation channel activity in the apical membrane of the outer medullary collecting duct of the inner stripe (OMCD(i)) using the patch-clamp technique. In freshly isolated and lumen-opened rabbit OMCD(i), we have observed a single channel conductance of 23.3 +/- 0.6 pS (n = 17) in cell-attached (c/a) patches with high KCl in the bath and in the pipette at room temperature. Channel open probability varied among patches from 0.06 +/- 0.01 at -60 mV (n = 5) to 0.31 +/- 0.04 at 60 mV (n = 6) and consistently increased upon membrane depolarization. In inside-out (i/o) patches with symmetrical KCl solutions, the channel conductance (22.8 +/- 0.8 pS; n = 10) was similar as in the c/a configuration. Substitution of the majority of Cl- with gluconate from KCl solution in the pipette and bath did not significantly alter reversal potential (E(rev)) or the channel conductance (19.7 +/- 1.1 pS in asymmetrical potassium gluconate, n = 4; 21.4 +/- 0.5 pS in symmetrical potassium gluconate, n = 3). Experiments with 10-fold lower KCl concentration in bath solution in i/o patches shifted E(rev) to near the E(rev) of K+. The estimated permeability of K+ vs. Cl- was over 10, and the conductance was 13.4 +/- 0.1 pS (n = 3). The channel did not discriminate between K+ and Na+, as evidenced by a lack of a shift in the E(rev) with different K+ and Na+ concentration solutions in i/o patches (n = 3). The current studies demonstrate the presence of cation channels in the apical membrane of native OMCD(i) cells that could participate in K+ secretion or Na+ absorption.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
1931-857X
pubmed:author
pubmed:issnType
Print
pubmed:volume
281
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
F48-55
pubmed:dateRevised
2011-4-28
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Apical membrane of native OMCD(i) cells has nonselective cation channels.
pubmed:affiliation
Department of Medicine, University of Florida, Gainsville 32610-0224, USA. xiasl@ufl.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.