Linked Life Data

7122214

Source:http://linkedlifedata.com/resource/pubmed/id/7122214

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1982-12-2
pubmed:abstractText
Previous experiments had demonstrated that cell chloride activities in early distal tubule cells of Amphiuma are above equilibrium distribution. Chloride activities fell sharply towards electrochemical equilibrium following perfusion of the tubular lumen with furosemide or with sodium-free solutions. These results suggested a furosemide-sensitive sodium chloride cotransport system in the luminal cell membrane. The present experiments were carried out to evaluate directly the electrochemical driving forces acting on sodium ions under similar experimental conditions. Intracellular sodium activity measurements were performed in the doubly-perfused kidney of Amphiuma by means of single-barreled liquid ion-exchange microelectrodes. Basolateral cell membrane potential and resistance ratio measurements of tubular cell membranes were also carried out under control conditions and after inhibition of chloride transport by luminal application of furosemide (5 . 10(-5) mol/l) or by omission of chloride. Control conditions were characterized by a steep downhill electrochemical gradient for sodium ions from lumen to cell. Inhibition of chloride transport led to a sharp decrease of intracellular sodium activity and to hyperpolarization of the peritubular membrane potential while the resistance ratio of the tubular cell membranes did not change significantly. These results demonstrate the presence of low cellular sodium activities in early distal tubule cells. The sharp decline of cell sodium after furosemide and after luminal chloride removal is consistent with inhibition of a sodium chloride cotransport system and continued peritubular sodium extrusion. The latter can increase the electrochemical gradient of sodium ions beyond that observed under control conditions.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0031-6768
pubmed:author
pubmed:issnType
Print
pubmed:volume
394
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
55-60
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1982
pubmed:articleTitle
Effects of inhibition of chloride transport on intracellular sodium activity in distal amphibian nephron.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't