Source:http://linkedlifedata.com/resource/pubmed/id/12065669
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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
3
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| pubmed:dateCreated |
2002-6-14
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| pubmed:abstractText |
Neuronal nicotinic acetylcholine receptors (nAChR) can regulate several neuronal processes through Ca2+-dependent mechanisms. The versatility of nAChR-mediated responses presumably reflects the spatial and temporal characteristics of local changes in intracellular Ca2+ arising from a variety of sources. The aim of this study was to analyse the components of nicotine-evoked Ca2+ signals in SH-SY5Y cells, by monitoring fluorescence changes in cells loaded with fluo-3 AM. Nicotine (30 microm) generated a rapid elevation in cytoplasmic Ca2+ that was partially and additively inhibited (40%) by alpha7 and alpha3beta2* nAChR subtype selective antagonists; alpha3beta4* nAChR probably account for the remaining response (60%). A substantial blockade (80%) by CdCl2 (100 microm) indicates that voltage-operated Ca2+ channels (VOCC) mediate most of the nicotine-evoked response, although the alpha7 selective antagonist alpha-bungarotoxin (40 nm) further decreased the CdCl2- resistant component. The elevation of intracellular Ca2+ levels provoked by nicotine was sustained for at least 10 min and required the persistent activation of nAChR throughout the response. Intracellular Ca2+ stores were implicated in both the initial and sustained nicotine-evoked Ca2+ responses, by the blockade observed after ryanodine (30 microm) and the inositoltriphosphate (IP3)-receptor antagonist, xestospongin-c (10 microm). Thus, nAChR subtypes are differentially coupled to specific sources of Ca2+: activation of nAChR induces a sustained elevation of intracellular Ca2+ levels which is highly dependent on the activation of VOCC, and also involves Ca2+ release from ryanodine and IP3-dependent intracellular stores. Moreover, the alpha7, but not alpha3beta2* nAChR, are responsible for a fraction of the VOCC-independent nicotine-evoked Ca2+ increase that appears to be functionally coupled to ryanodine sensitive Ca2+ stores.
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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/Aniline Compounds,
http://linkedlifedata.com/resource/pubmed/chemical/Calcium,
http://linkedlifedata.com/resource/pubmed/chemical/Calcium Channels,
http://linkedlifedata.com/resource/pubmed/chemical/Enzyme Inhibitors,
http://linkedlifedata.com/resource/pubmed/chemical/Fluo-3,
http://linkedlifedata.com/resource/pubmed/chemical/Fluorescent Dyes,
http://linkedlifedata.com/resource/pubmed/chemical/Macrocyclic Compounds,
http://linkedlifedata.com/resource/pubmed/chemical/Mecamylamine,
http://linkedlifedata.com/resource/pubmed/chemical/Nicotine,
http://linkedlifedata.com/resource/pubmed/chemical/Nicotinic Agonists,
http://linkedlifedata.com/resource/pubmed/chemical/Nicotinic Antagonists,
http://linkedlifedata.com/resource/pubmed/chemical/Oxazoles,
http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Nicotinic,
http://linkedlifedata.com/resource/pubmed/chemical/Ryanodine,
http://linkedlifedata.com/resource/pubmed/chemical/Xanthenes,
http://linkedlifedata.com/resource/pubmed/chemical/xestospongin A
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| pubmed:status |
MEDLINE
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| pubmed:month |
May
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| pubmed:issn |
0022-3042
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| pubmed:author | |
| pubmed:issnType |
Print
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| pubmed:volume |
81
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| pubmed:owner |
NLM
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| pubmed:authorsComplete |
Y
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| pubmed:pagination |
606-14
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| pubmed:dateRevised |
2006-11-15
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| pubmed:meshHeading |
pubmed-meshheading:12065669-Aniline Compounds,
pubmed-meshheading:12065669-Calcium,
pubmed-meshheading:12065669-Calcium Channels,
pubmed-meshheading:12065669-Calcium Signaling,
pubmed-meshheading:12065669-Enzyme Inhibitors,
pubmed-meshheading:12065669-Fluorescent Dyes,
pubmed-meshheading:12065669-Humans,
pubmed-meshheading:12065669-Intracellular Fluid,
pubmed-meshheading:12065669-Macrocyclic Compounds,
pubmed-meshheading:12065669-Mecamylamine,
pubmed-meshheading:12065669-Neuroblastoma,
pubmed-meshheading:12065669-Neurons,
pubmed-meshheading:12065669-Nicotine,
pubmed-meshheading:12065669-Nicotinic Agonists,
pubmed-meshheading:12065669-Nicotinic Antagonists,
pubmed-meshheading:12065669-Oxazoles,
pubmed-meshheading:12065669-Receptors, Nicotinic,
pubmed-meshheading:12065669-Ryanodine,
pubmed-meshheading:12065669-Tumor Cells, Cultured,
pubmed-meshheading:12065669-Xanthenes
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| pubmed:year |
2002
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| pubmed:articleTitle |
Intracellular Ca2+ signals evoked by stimulation of nicotinic acetylcholine receptors in SH-SY5Y cells: contribution of voltage-operated Ca2+ channels and Ca2+ stores.
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| pubmed:affiliation |
Department of Biology and Biochemistry, University of Bath, Bath, UK.
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| pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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