Linked Life Data

16129693

Source:http://linkedlifedata.com/resource/pubmed/id/16129693

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
43
pubmed:dateCreated
2005-10-24
pubmed:abstractText
S100A1 is an EF-hand type Ca2+-binding protein with a muscle-specific expression pattern. The highest S100A1 protein levels are found in cardiomyocytes, and it is expressed already at day 8 in the heart during embryonic development. Since S100A1 is known to be involved in the regulation of Ca2+ homeostasis, we tested whether extracellular S100A1 plays a role in regulating the L-type Ca2+ current (I(Ca)) in ventricular cardiomyocytes. Murine embryonic (day 16.5 postcoitum) ventricular cardiomyocytes were incubated with S100A1 (0.001-10 microM) for different time periods (20 min to 48 h). I(Ca) density was found to be significantly increased as early as 20 min (from -10.8 +/- 1 pA/pF, n = 18, to -22.9 +/- 1.4 pA/pF; +112.5 +/- 13%, n = 9, p < 0.001) after the addition of S100A1 (1 microM). S100A1 also enhanced I(Ca) current density in neonatal rat cardiomyocytes. Fluorescence and capacitance measurements evidenced a fast translocation of rhodamine-coupled S100A1 from the extracellular space into cardiomyocytes. S100A1 treatment did not affect cAMP levels. However, protein kinase inhibitor, a blocker of cAMP-dependent protein kinase A (PKA), abolished the S100A1-induced enhancement of I(Ca). Accordingly, measurements of PKA activity yielded a significant increase in S100A1-treated cardiomyocytes. In vitro reconstitution assays further demonstrated that S100A1 enhanced PKA activity. We conclude that the Ca2+-binding protein S100A1 augments transsarcolemmal Ca2+ influx via an increase of PKA activity in ventricular cardiomyocytes and hence represents an important regulator of cardiac function.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
28
pubmed:volume
280
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
36019-28
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed-meshheading:16129693-Animals, pubmed-meshheading:16129693-Calcium, pubmed-meshheading:16129693-Calcium Channels, L-Type, pubmed-meshheading:16129693-Calcium-Binding Proteins, pubmed-meshheading:16129693-Cells, Cultured, pubmed-meshheading:16129693-Cyclic AMP, pubmed-meshheading:16129693-Cyclic AMP-Dependent Protein Kinases, pubmed-meshheading:16129693-Cytosol, pubmed-meshheading:16129693-Electrophysiology, pubmed-meshheading:16129693-Endocytosis, pubmed-meshheading:16129693-Kinetics, pubmed-meshheading:16129693-Mice, pubmed-meshheading:16129693-Muscles, pubmed-meshheading:16129693-Myocytes, Cardiac, pubmed-meshheading:16129693-Protein Transport, pubmed-meshheading:16129693-Rats, pubmed-meshheading:16129693-Rats, Sprague-Dawley, pubmed-meshheading:16129693-Rhodamines, pubmed-meshheading:16129693-S100 Proteins, pubmed-meshheading:16129693-Signal Transduction, pubmed-meshheading:16129693-Spectrometry, Fluorescence, pubmed-meshheading:16129693-Time Factors
pubmed:year
2005
pubmed:articleTitle
S100A1 enhances the L-type Ca2+ current in embryonic mouse and neonatal rat ventricular cardiomyocytes.
pubmed:affiliation
Institute of Neurophysiology, University of Cologne, Cologne 50931, Germany. michael.reppel@uni-koeln.de
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't