Linked Life Data

2783910

Source:http://linkedlifedata.com/resource/pubmed/id/2783910

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1989-4-6
pubmed:abstractText
T51B rat liver epithelial cells were stimulated with extracellular ATP. Changes in cytoplasmic free Ca2+ concentration [( Ca2+]i) were measured by fura-2 both in a large population of cells on coverslips in a cuvette and in single cells in a microscopic system. Extracellular ATP evoked a prompt increase in [Ca2+]i in both the presence and absence of extracellular Ca2+, although the effect was less pronounced in the latter case. These findings indicate that at least part of the [Ca2+]i increase is due to mobilization of intracellularly bound calcium. Stimulation with ATP did not mobilize the total pool of intracellular releasable Ca2+, as evidenced from experiments where subsequent addition of ionomycin evoked a pronounced increase in [Ca2+]i in the absence of extracellular Ca2+. The effect of ATP was maintained at room temperature but was markedly impaired in the absence of continuous stirring of the buffer solution. In the absence of stirring, ATP had to be increased to the millimolar range in order to evoke a pronounced effect. Single cell measurements revealed a heterogenous Ca2+ response to ATP, with some cells failing to respond with a detectable increase in [Ca2+]i. The actual increase in [Ca2+]i was not uniform throughout the cytoplasm, but seemed to start in one part of the cell. Even if part of the [Ca2+]i increase might be accounted for by ATP promoting the hydrolysis of phosphatidylinositol 4,5-bisphosphate and thereby a generation of InsP3 and diacylglycerol, there was no initiation of DNA synthesis under the present conditions. Hence, extracellular growth factors exert either a quantitative difference in second messenger production or additional stimulatory effects by activating intracellular signal pathways beyond these represented by [Ca2+]i and protein kinase C.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0014-4827
pubmed:author
pubmed:issnType
Print
pubmed:volume
181
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
245-55
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Extracellular ATP mobilizes intracellular Ca2+ in T51B rat liver epithelial cells: a study involving single cell measurements.
pubmed:affiliation
Cancer Research Center of Hawaii, Honolulu 96813.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't