Linked Life Data

8781189

Source:http://linkedlifedata.com/resource/pubmed/id/8781189

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1996-11-7
pubmed:abstractText
We performed experiments using the calcium indicator Indo-1 to determine the relative roles of the sarcolemmal mechanisms involved in the regulation of diastolic intracellular calcium concentration ([Ca2+]i) in trabeculae from the rat heart. Ryanodine was used to eliminate sarcoplasmic reticulum (SR) function. In the functional absence of the SR, 76.8 +/- 3.9% of the calcium was extruded by the Na-Ca exchange carrier in the [Ca2+]i range of diastolic concentration +/- 200-400 nM. This was assessed by measuring the recovery of [Ca2+]i from small perturbations in the presence and absence of extracellular sodium. The steady-state relationship between [Ca2+]o and [Ca2+]i was linear over the range of 1-40 mM, a 20-fold increase of [Ca2+]o produced a 1.97-fold +/- 0.13-fold increase in [Ca2+]i (n = 5). In the absence of extracellular sodium raising [Ca2+]o had a variable effect. In some preparations there was little change of [Ca2+]i while in others the response was almost as large as in control conditions. We conclude that the Na-Ca exchanger contributes approximately 77% of sarcolemmal calcium extrusion following small perturbations in [Ca2+]i and that this fraction does not diminish as the [Ca2+]i declines. In addition we have shown a sodium-independent entry of calcium into quiescent cardiac muscle under resting conditions.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0031-6768
pubmed:author
pubmed:issnType
Print
pubmed:volume
432
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
961-9
pubmed:dateRevised
2009-9-29
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
The sarcolemmal mechanisms involved in the control of diastolic intracellular calcium in isolated rat cardiac trabeculae.
pubmed:affiliation
Department of Veterinary Preclinical Sciences, University of Liverpool, PO Box 147, Liverpool, L69 3BX, UK.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't