Linked Life Data

15117716

Source:http://linkedlifedata.com/resource/pubmed/id/15117716

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2004-8-19
pubmed:abstractText
Both the cardiac action potential duration (APD) (0.6-1 s) and resting heart rate (30-40 beats/min) in the horse are significantly different from humans and smaller mammals, including the rabbit. This would be anticipated to have consequences for excitation-contraction (EC) coupling and require adaptation of the individual processes involved. The sarcoplasmic reticulum (SR) is one of the main components involved in EC coupling. This study examines and compares the activity of this organelle in the horse with that of the rabbit. In particular, the study focuses on SR Ca2+ release via the Ca2+ release channel/ryanodine receptor (RyR2) and Ca2+ uptake via the sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA) pump. Isolated cardiomyocytes from both horse and rabbit hearts were permeabilized, bathed in a mock intracellular solution, and exposed to a specified [Ca2+]. Rabbit cardiomyocytes exposed to 260 nM [Ca2+] produced spontaneous Ca2+ release and propagated Ca2+ waves. Horse cells failed to produce Ca2+ waves; instead, only local release in the form of Ca2+ sparks was evident. However, at 550 nM [Ca2+], Ca2+ waves were produced in both species. Ca2+ waves were four times less frequent yet approximately 1.5 times greater in amplitude in the horse compared with the rabbit. Ca2+ wave velocity was comparable between the species. The reason for this disparity in Ca2+ wave characteristics is unknown. Separate measurements of oxalate-supported Ca2+ uptake into the SR suggest that both horse and rabbit cardiomyocytes have comparable levels SERCA activity. The possible reasons for the observed differences in SR Ca2+ release between the horse and rabbit are discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0363-6135
pubmed:author
pubmed:issnType
Print
pubmed:volume
287
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
H1149-59
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Comparison of Ca2+ release and uptake characteristics of the sarcoplasmic reticulum in isolated horse and rabbit cardiomyocytes.
pubmed:affiliation
Institute of Comparative Medicine, University of Glasgow Veterinary School, University of Glasgow, Glasgow G12 8QQ, UK.
pubmed:publicationType
Journal Article, Comparative Study, In Vitro, Research Support, Non-U.S. Gov't