Linked Life Data

11150292

Source:http://linkedlifedata.com/resource/pubmed/id/11150292

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
14
pubmed:dateCreated
2001-4-3
pubmed:abstractText
Using an antisense strategy, we have previously shown that in vascular myocytes, subtypes 1 and 2 of ryanodine receptors (RYRs) are required for Ca(2+) release during Ca(2+) sparks and global Ca(2+) responses, evoked by activation of voltage-gated Ca(2+) channels, whereas RYR subtype 3 (RYR3) has no contribution. Here, we investigated the effects of increased Ca(2+) loading of the sarcoplasmic reticulum (SR) on the RYR-mediated Ca(2+) responses and the role of the RYR3 by injecting antisense oligonucleotides targeting the RYR subtypes. RYR3 expression was demonstrated by immunodetection in both freshly dissociated and cultured rat portal vein myocytes. Confocal Ca(2+) measurements revealed that the number of cells showing spontaneous Ca(2+) sparks was strongly increased by superfusing the vascular myocytes in 10 mm Ca(2+)-containing solution. These Ca(2+) sparks were blocked after inhibition of RYR1 or RYR2 by treatment with antisense oligolucleotides but not after inhibition of RYR3. In contrast, inhibition of RYR3 reduced the global Ca(2+) responses induced by caffeine and phenylephrine, indicating that RYR3 participated together with RYR1 and RYR2 to these Ca(2+) responses in Ca(2+)-overloaded myocytes. Ca(2+) transients evoked by photolysis of caged Ca(2+) with increasing flash intensities were also reduced after inhibition of RYR3 and revealed that the [Ca(2+)](i) sensitivity of RYR3 would be similar to that of RYR1 and RYR2. Our results show that, under conditions of increased SR Ca(2+) loading, the RYR3 becomes activable by caffeine and local increases in [Ca(2+)](i).
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
6
pubmed:volume
276
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11257-64
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Contribution of ryanodine receptor subtype 3 to ca2+ responses in Ca2+-overloaded cultured rat portal vein myocytes.
pubmed:affiliation
Laboratoire de Signalisation et Interactions Cellulaires, CNRS UMR 5017, Université de Bordeaux II, 146 rue Léo Saignat, Bordeaux Cedex 33076, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't