Linked Life Data

12208231

Source:http://linkedlifedata.com/resource/pubmed/id/12208231

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2002-9-4
pubmed:abstractText
The kinetics of the intracellular Ca2+ concentration ([Ca2+]i) of vascular smooth muscle cells (VSMCs) in rat small mesenteric arteries was investigated by confocal laser scanning microscopy using the fluorescent Ca2+ indicator fluo-3 AM. One micromole noradrenaline (NA) induced randomly distributed transient elevations of [Ca2+]i in several single VSMCs which were weakly temporally coupled. Higher NA concentrations of 3 or 10 microM, however, induced strongly synchronised [Ca2+]i oscillations in VSMCs. In preparations with intact endothelium, the synchronisation of [Ca2+]i signals was attenuated by acetylcholine (ACh) but augmented by the NO synthase antagonist L-NAME, pointing to a desynchronising effect of the endothelium even under basal conditions. In preparations with or without intact endothelium sodium nitroprusside (SNP) as well as the gap-junction uncoupler heptanol reversibly desynchronised the [Ca2+]i transients. The effect of ACh but not that of SNP was influenced by L-NAME. Propagated intracellular [Ca2+]i waves had a velocity of 25 microm/s. The phase shift of [Ca2+]i oscillations between single VSMCs were maximally 2s and independent of the distance of up to 90 microm between individual cells. Therefore, we consider intercellular [Ca2+]i waves to be too slow to account for the synchronisation of [Ca2+]i oscillations. We conclude that the coupling of [Ca2+]i signals in vascular smooth muscle cells is not constant but highly regulated by NA and by endothelium derived NO. Oscillations of vessel contraction at high sympathetic tone may be induced by synchronisation of [Ca2+]i transients of distinct VSMCs whereas endothelium derived NO inhibits vasomotion by desynchronising [Ca2+]i transients of single VSMCs.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0143-4160
pubmed:author
pubmed:issnType
Print
pubmed:volume
32
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
105-20
pubmed:dateRevised
2009-11-3
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Desynchronising effect of the endothelium on intracellular Ca2+ concentration dynamics in vascular smooth muscle cells of rat mesenteric arteries.
pubmed:affiliation
Julius-Bernstein-Institut für Physiologie, Martin-Luther-Universität Halle-Wittenberg, Magdeburger Strasse 6, D-06097 Halle/Saale, Germany.
pubmed:publicationType
Journal Article, In Vitro