Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1 Pt 2
pubmed:dateCreated
1985-8-13
pubmed:abstractText
The present study evaluated the use of nuclear magnetic resonance (NMR) spectroscopy to monitor directly and continuously intracellular sodium levels in rabbit renal cortical tubule suspensions. When the paramagnetic shift reagent dysprosium tripolyphosphate was added to the extracellular medium it was possible to resolve signals from intracellular and extracellular sodium without adversely affecting cellular viability. An efflux of intracellular sodium against a significant concentration gradient was observed when sodium-loaded cells were warmed from 4 to 37 degrees C. At 37 degrees C in steady state, inhibition of Na+-K+-ATPase activity by ouabain increased intracellular sodium content in a dose-dependent and time-dependent manner. A biphasic time course of increased intracellular sodium following ouabain (10(-3) M) suggested that the sodium permeability of the plasma membrane may decrease following pump inhibition, thus limiting sodium influx. Nystatin, an agent known to facilitate sodium entry across cell membranes, increased intracellular sodium fivefold. In another series of experiments several maneuvers were performed to ascertain the fraction of intracellular sodium that was NMR visible. Quantitative assessment of either an efflux or influx of sodium indicated that the NMR visibility of the transported sodium was 100%. Furthermore, disruption of the cell membranes with Triton X-100 showed that the entire pool of intracellular sodium was 100% NMR visible.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
249
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
F160-8
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
NMR measurements of intracellular sodium in the rabbit proximal tubule.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.