Linked Life Data

15623437

Source:http://linkedlifedata.com/resource/pubmed/id/15623437

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2004-12-29
pubmed:abstractText
Neuropeptide Y (NPY) is the most abundant peptide in the mammalian heart, but its cardiac actions are not fully understood. Here we investigate the effect of NPY in intracellular Ca2+ release, using isolated rat cardiac myocytes and confocal microscopy. Cardiac myocytes were field-stimulated at 1 Hz. The evoked [Ca2+]i transient was of higher amplitude and of faster decay in the presence of 100 nM NPY. Cell contraction was also increased by NPY. We analyzed the occurrence of Ca2+ sparks and their characteristics after NPY application. NPY significantly increased Ca2+ sparks frequency in quiescent cells. The Ca2+ spark amplitude was enhanced by NPY but the other characteristics of Ca2+ sparks were not significantly altered. Because cardiac myocytes express both Y1 and Y2 NPY receptors, we repeated the experiments in the presence of the receptor blockers, BIBP3226 and BIIE0246. We found that Y1 NPY receptor blockade completely inhibited NPY effects on [Ca2+]i transient. PTX-sensitive G-proteins and/or phospholypase C (PLC) have been invoked to mediate NPY effects in other cell types. We tested these two hypotheses. In PTX-treated myocytes NPY was still effective, which suggests that the observed NPY actions are not mediated by PTX-sensitive G-proteins. In contrast, the increase in [Ca2+]i transient by NPY was completely inhibited by the PLC inhibitor U73122. In conclusion, we find that NPY has a positive inotropic effect in isolated rat cardiac myocytes, which involves increase in Ca2+ release after activation of Y1 NPY receptor and subsequent stimulation of PLC.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0022-2828
pubmed:author
pubmed:issnType
Print
pubmed:volume
38
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
205-12
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Neuropeptide Y rapidly enhances [Ca2+]i transients and Ca2+ sparks in adult rat ventricular myocytes through Y1 receptor and PLC activation.
pubmed:affiliation
Institute of Pharmacology and Toxicology, CSIC-UCM, Madrid, Spain.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't