Linked Life Data

1744175

Source:http://linkedlifedata.com/resource/pubmed/id/1744175

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1992-1-15
pubmed:abstractText
The aim of the present study was to investigate the effect of membrane depolarization on ATP-induced changes in intracellular Ca2+ ([Ca2+]i) and the refilling of intracellular Ca2+ stores in thyroid follicular FRTL-5 cells. Depolarizing the cells with 50 mM K+, an amount sufficient to almost totally depolarize the cells as determined by bisoxonal, significantly reduced the ATP-induced uptake of 45Ca2+. This effect was not dependent on an enhanced efflux of Ca2+, as no difference in the ATP-induced efflux of 45Ca2+ was obtained between control cells and depolarized cells. The ATP-induced transient increase in [Ca2+]i in Fura-2 loaded cells was not altered by depolarization, whereas the ATP-induced plateau in [Ca2+]i was decreased compared with control cells. Furthermore, in cells stimulated with ATP in a Ca(2+)-free buffer, readdition of Ca2+ after the termination of the ATP response induced a decreased response in [Ca2+]i in depolarized cells. Refilling of intracellular Ca2+ stores was investigated by first stimulating the cells with noradrenaline (NA). The effect of NA was then terminated with prazosin, and the cells restimulated with ATP. In cells depolarized with high K+, the response to ATP was decreased compared with that seen in control cells. The results thus suggest that both the ATP-induced influx of extracellular Ca2+ and the refilling of intracellular Ca2+ stores is decreased in depolarized FRTL-5 cells.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9541
pubmed:author
pubmed:issnType
Print
pubmed:volume
149
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
485-91
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Depolarization of the membrane potential decreases the ATP-induced influx of extracellular Ca2+ and the refilling of intracellular Ca2+ stores in rat thyroid FRTL-5 cells.
pubmed:affiliation
Endocrine Research Laboratory, University of Helsinki, Finland.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't