Linked Life Data

6276550

Source:http://linkedlifedata.com/resource/pubmed/id/6276550

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
1982-4-12
pubmed:abstractText
Near-instantaneous current-voltage relationships and shot-noise analysis of amiloride-induced current fluctuations were used to estimate apical membrane permeability to Na (PNa), intraepithelial Na activity (Nac), single-channel Na currents (i) and the number of open (conducting) apical Na channels (N0), in the urinary bladder of the toad (Bufo marinus). To facilitate voltage-clamping of the apical membrane, the serosal plasma membranes were depolarized by substitution of a high KCl (85 mM) sucrose (50 mM) medium for the conventional Na-Ringer's solution on the serosal side. Aldosterone (5 X 10(-7) M, serosal side only) elicited proportionate increases in the Na-specific current (INa and in PNa, with no significant change in the dependence of PNa on mucosal Na (Nao). PNa and the control of PNa by aldosterone were substrate-dependent: In substrate-depleted bladders, pretreatment with aldosterone markedly augmented the response to pyruvate (7.5 X 10(-3) M) which evoked coordinate and equivalent increases in INa and PNa. The aldosterone-dependent increase in PNa was a result of an equivalent increase in the area density of conducting apical Na channels. The computed single-channel current did not change. We propose that, following aldosterone-induced protein synthesis, there is a reversible metabolically-dependent recruitment of preexisting Na channels from a reservoir of electrically undetectable channels. The results do not exclude the possibility of a complementary induction of Na-channel synthesis.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0022-2631
pubmed:author
pubmed:issnType
Print
pubmed:volume
64
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
91-102
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1982
pubmed:articleTitle
Aldosterone control of the density of sodium channels in the toad urinary bladder.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't