Linked Life Data

16839456

Source:http://linkedlifedata.com/resource/pubmed/id/16839456

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2006-9-15
pubmed:abstractText
We previously estimated the myofilament responsiveness to Ca(2+) in isolated intact ventricular myocytes, using the steady-state relationship between cytosolic Ca(2+) concentration ([Ca(2+)](i)) and cell-shortening during tetanus (Ca-L trajectory). This method was useful and easy; however, it could not be used for a high dose of Ca sensitizer because the instantaneous plots after the application of Ca sensitizer did not make a fixed point of shortening (we used 5% shortening). Therefore we must produce another method to investigate Ca(2+) responsiveness. For an estimation of a wider range of the Ca-L trajectory, we fitted the Ca-L trajectory data with the Hill equation to construct the Ca-shortening curve. To fit this curve, we measured the maximal shortening, which was on average 31.6%. The value of [Ca(2+)](i) to produce the half-maximal shortening (Ca(50)) was dose-dependently decreased by EMD57033 (sensitization). Either isoproterenol or 3-isobutyl-1-methylxanthine increased Ca(50) (desensitization) with a concomitant increase in intracellular c-AMP. EMD57439, a selective PDE-III inhibitor, did not significantly increase the c-AMP concentration and produced little change in Ca(50). These results are in agreement with previous reports with skinned or intact multicellular preparations. The Ca-shortening curve constructed in intact cardiac myocytes can be used to estimate the myofibrillar responsiveness to Ca(2+) in a wide range of [Ca(2+)](i).
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
1880-6546
pubmed:author
pubmed:issnType
Print
pubmed:volume
56
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
219-26
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Use of the Ca-shortening curve to estimate the myofilament responsiveness to Ca2+ in tetanized rat ventricular myocytes.
pubmed:affiliation
Department of Physiology (II), The Jikei University School of Medicine, 3-25-8 Nishishinbashi, Minato-ku, Tokyo 105-8461, Japan. kusakari@jikei.ac.jp
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't