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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
10
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pubmed:dateCreated |
1991-7-17
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pubmed:abstractText |
Using single-cell ratio imaging of Fura-2-loaded neutrophils, we demonstrate that the heterogeneity and asynchrony of the oxidase response originates from variability in the timing and magnitude of the cytosolic free Ca2+ signal. The Ca2+ signals from individual cells could be classified into four types: (a) type 1, a transient rise in Ca2+ occurring within 6 s; (b) type 2, an oscillating cytosolic free Ca2+; (c) type 3, a latent Ca2+ transient significantly delayed (21-56 s); and (d) type 4, no significant Ca2+ rise. These response types accounted for approximately 41%, 15%, 26% and 18% of the population respectively for stimulation with 1 microM f-met-leu-phe peptide (n = 27) and 52.5%, 15%, 11.5% and 21% respectively for 0.1 microM f-met-leu-phe peptide (n = 52). The oxidase in neutrophils in which the cytosolic free Ca2+ concentration rose to greater than 250 nM always became activated. In the presence of extracellular Ca2+, cytosolic Ca2+ rose uniformly throughout the cell, whereas in the absence of extracellular Ca2+, a localised Ca2+ 'cloud' was observed in approximately 30% of cells. A localised activation of the oxidase accompanied the presence of the Ca2+ 'cloud' when the 250 nM Ca2+ threshold was exceeded. The data presented here therefore demonstrate a tight coupling in individual neutrophils between an elevation in cytosolic free Ca2+ above a threshold of 250 nM and activation of the oxidase.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Calcium,
http://linkedlifedata.com/resource/pubmed/chemical/Formazans,
http://linkedlifedata.com/resource/pubmed/chemical/N-Formylmethionine...,
http://linkedlifedata.com/resource/pubmed/chemical/Nitroblue Tetrazolium,
http://linkedlifedata.com/resource/pubmed/chemical/Oxidoreductases,
http://linkedlifedata.com/resource/pubmed/chemical/Superoxides
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pubmed:status |
MEDLINE
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pubmed:issn |
0143-4160
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
11
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
655-63
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:1965710-Biological Transport,
pubmed-meshheading:1965710-Calcium,
pubmed-meshheading:1965710-Cytosol,
pubmed-meshheading:1965710-Enzyme Activation,
pubmed-meshheading:1965710-Formazans,
pubmed-meshheading:1965710-Humans,
pubmed-meshheading:1965710-Microscopy, Fluorescence,
pubmed-meshheading:1965710-N-Formylmethionine Leucyl-Phenylalanine,
pubmed-meshheading:1965710-Neutrophils,
pubmed-meshheading:1965710-Nitroblue Tetrazolium,
pubmed-meshheading:1965710-Oxidoreductases,
pubmed-meshheading:1965710-Superoxides
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pubmed:articleTitle |
Oxidase activation in individual neutrophils is dependent on the onset and magnitude of the Ca2+ signal.
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pubmed:affiliation |
Department of Surgery, University of Wales College of Medicine, Cardiff, UK.
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pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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