Linked Life Data

7943212

Source:http://linkedlifedata.com/resource/pubmed/id/7943212

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3 Pt 1
pubmed:dateCreated
1994-10-24
pubmed:abstractText
Dark cell epithelium secretes K+ into the lumen of the vestibular labyrinth by a previously unidentified apical transport mechanism. Previous single-channel patch-clamp studies demonstrated nonselective cation channels and maxi-K+ channels in the apical membrane, but in too low a density to account for transepithelial K+ transport. In this report, we demonstrated with the cell-attached macro-patch-clamp technique an outward apical membrane current at 0-mV pipette voltage, which was stimulated by elevating bath K+ concentration from 3.6 to 25 mM and inhibited by 10 microM bumetanide, similar to their known effects on transepithelial short-circuit current and K+ secretion. Furthermore, the patch current was activated over several seconds by a sustained depolarization and deactivated over several hundred milliseconds by a hyperpolarization. Current-voltage relationships from tail currents were obtained with either NaCl or KCl in the pipette. Depolarization from -40 to +40 mV led to an increased conductance by a factor of 7.3 +/- 1.7 (n = 7) and 19.2 +/- 7.6 (n = 6) for NaCl and KCl, respectively, and to a reversal voltage near the presumed equilibrium potential for K+. The results demonstrate that dark cell K+ secretion occurs via K(+)-selective channels with characteristics similar to those associated with the IsK protein.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
267
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
C857-64
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Slowly activating voltage-dependent K+ conductance is apical pathway for K+ secretion in vestibular dark cells.
pubmed:affiliation
Biophysics Laboratory, Boys Town National Research Hospital, Omaha, Nebraska 68131.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.