Linked Life Data

6604061

Source:http://linkedlifedata.com/resource/pubmed/id/6604061

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1983-10-28
pubmed:abstractText
Cell swelling and elevated intracellular Ca2+ increase K+ permeability in lymphocytes. Experiments were performed to test whether these effects can also be elicited in isolated plasma membrane vesicles. Rabbit thymocytes, used as a source of membrane vesicles, were found to regain their volume after swelling in hypotonic, low-K+ media. This regulatory volume decrease (RVD) was inhibited by quinine and trifluoperazine, but not affected by ouabain. Both efflux and uptake of K+ (86Rb) were stimulated by hypotonicity. Addition of A23187 plus Ca2+ also increased 86Rb fluxes. Ca2+- and volume-induced 86Rb fluxes were also studied in isolated membranes. A plasma membrane-rich vesicle fraction, enriched over 11-fold in 5'-nucleotidase, was isolated from thymocytes. The vesicles were about 35% inside-out and trapped 86Rb in an osmotically active compartment of approximately 1.3 microliter/mg protein. Equilibrium exchange fluxes of 86Rb in the vesicles were unaffected by Ca2+ with or without A23187. Calmodulin had no effect on 86Rb permeability but stimulated ATP-dependent Ca2+ accumulation. Hypotonic swelling increased both uptake and efflux of 86Rb from vesicles. However, this increase was not blocked by either quinine or trifluoperazine, was not specific for K+ (86Rb), and is probably unrelated to RVD. It is concluded that components essential for the volume- and Ca2+-induced changes in K+ permeability are lost or inactivated during membrane isolation. An intact cytoarchitecture may be required for RVD.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0021-9541
pubmed:author
pubmed:issnType
Print
pubmed:volume
116
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
352-62
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1983
pubmed:articleTitle
Induction of 86Rb fluxes by Ca2+ and volume changes in thymocytes and their isolated membranes.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't