Linked Life Data

7526849

Source:http://linkedlifedata.com/resource/pubmed/id/7526849

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1994-12-20
pubmed:abstractText
In a previous study it was found that the expression of the exogenous fMet-Leu-Phe-receptor (NFPR) in the insulin-secreting cell line RINm5F mediates inhibition of hormone release and additionally raises cytosolic calcium concentration ([Ca2+]i) by activating phospholipase C (PLC) in a pertussis-toxin (PTX)-sensitive manner. We investigated whether an endogenous receptor could elicit similar effects and examined the interaction with PTX-insensitive signalling pathways. The hormone galanin inhibited insulin release at subnanomolar concentrations and increased [Ca2+]i, mainly by a PTX-sensitive mechanism with an EC50 (50 nM) comparable with that for hyperpolarization of membrane potential. The effect of galanin or fMet-Leu-Phe on [Ca2+]i was inhibited by pre-activation of the P2-receptor by ATP, which mobilizes calcium in a PTX-insensitive fashion. Simultaneous activation of the P2- and peptide receptors caused additive increases in [Ca2+]i saturating at a calcium concentration corresponding to the optimal ATP response. This suggests a specific convergence of PTX-sensitive and -insensitive pathways. In contrast, galanin and FMLP inhibited the insulin secretion induced by ATP (1-100 microM), but only when added prior to the nucleotide. In permeabilized cells, FMLP added after the calcium stimulus still inhibited secretion, indicating that the inefficacy observed in intact cells was not due to the rapid ATP-evoked rise in [Ca2+]i. Thus, (i) insulin-secreting cells possess an endogenous PTX-sensitive pathway mobilizing [Ca2+]i, (ii) inhibitory hormones preferentially activate different effectors depending on the agonist concentration and (iii) activation of NFPR or galanin receptor reveals an unusual dissociation between [Ca2+]i rises and insulin secretion, pointing towards an overriding inhibitory control of exocytosis.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-1280361, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-1311307, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-1319994, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-1322796, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-1333955, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-1335363, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-1465133, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-1465134, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-15336043, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-1680855, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-1995609, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-2119205, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-2138778, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-2450047, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-2454675, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-2460348, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-2468476, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-2468668, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-2469602, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-2470586, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-2506013, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-2837460, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-2991734, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-3107454, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-3522567, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-6118266, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-7682064, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-7688958, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-8382479, http://linkedlifedata.com/resource/pubmed/commentcorrection/7526849-8392932
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0264-6021
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
303 ( Pt 3)
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
885-91
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Regulation of cytosolic calcium and insulin secretion by galanin and ATP receptors: interactions of pertussis-toxin-sensitive and -insensitive signalling pathways.
pubmed:affiliation
Département de Médecine, Université de Genéve, Switzerland.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't