Linked Life Data

12805242

Source:http://linkedlifedata.com/resource/pubmed/id/12805242

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2003-7-25
pubmed:abstractText
To evaluate the effect of sorcin on cardiac excitation-contraction coupling, adult rabbit ventricular myocytes were transfected with a recombinant adenovirus coding for human sorcin (Ad-sorcin). A beta-galactosidase adenovirus (Ad-LacZ) was used as a control. Fractional shortening in response to 1-Hz field stimulation (at 37 degrees C) was significantly reduced in Ad-sorcin-transfected myocytes compared with control myocytes (2.10+/-0.05% [n=311] versus 2.42+/-0.06% [n=312], respectively; P<0.001). Action potential duration (at 20 degrees C) was significantly less in the Ad-sorcin group (458+/-22 ms, n=11) compared with the control group (520+/-19 ms, n=10; P<0.05). In voltage-clamped, fura 2-loaded myocytes (20 degrees C), a reduced peak-systolic and end-diastolic [Ca2+]i was observed after Ad-sorcin transfection. L-type Ca2+ current amplitude and time course were unaffected. Caffeine-induced Ca2+ release from the sarcoplasmic reticulum (SR) and the accompanying inward Na+-Ca2+ exchanger (NCX) current revealed a significantly lower SR Ca2+ content and faster Ca2+-extrusion kinetics in Ad-sorcin-transfected cells. Higher NCX activity after Ad-sorcin transfection was confirmed by measuring the NCX current-voltage relationship. beta-Escin-permeabilized rabbit cardiomyocytes were used to study the effects of sorcin overexpression on Ca2+ sparks imaged with fluo 3 at 145 to 160 nmol/L [Ca2+] using a confocal microscope. Under these conditions, caffeine-mediated SR Ca2+ release was not different between the two groups. Spontaneous spark frequency, duration, width, and amplitude were lower in sorcin-overexpressing myocytes. In summary, sorcin overexpression in rabbit cardiomyocytes decreased Ca2+-transient amplitude predominantly by lowering SR Ca2+ content via increased NCX activity. The effect of sorcin overexpression on Ca2+ sparks indicates an effect on the ryanodine receptor that may also influence excitation-contraction coupling.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
1524-4571
pubmed:author
pubmed:issnType
Electronic
pubmed:day
25
pubmed:volume
93
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
132-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:12805242-Adenoviridae, pubmed-meshheading:12805242-Animals, pubmed-meshheading:12805242-Caffeine, pubmed-meshheading:12805242-Calcium, pubmed-meshheading:12805242-Calcium Signaling, pubmed-meshheading:12805242-Calcium-Binding Proteins, pubmed-meshheading:12805242-Cells, Cultured, pubmed-meshheading:12805242-Escin, pubmed-meshheading:12805242-Gene Expression, pubmed-meshheading:12805242-Gene Transfer Techniques, pubmed-meshheading:12805242-Humans, pubmed-meshheading:12805242-Intracellular Fluid, pubmed-meshheading:12805242-Myocardial Contraction, pubmed-meshheading:12805242-Myocytes, Cardiac, pubmed-meshheading:12805242-Nickel, pubmed-meshheading:12805242-Patch-Clamp Techniques, pubmed-meshheading:12805242-Permeability, pubmed-meshheading:12805242-RNA, Messenger, pubmed-meshheading:12805242-Rabbits, pubmed-meshheading:12805242-Sarcolemma, pubmed-meshheading:12805242-Sarcoplasmic Reticulum
pubmed:year
2003
pubmed:articleTitle
Effects of adenovirus-mediated sorcin overexpression on excitation-contraction coupling in isolated rabbit cardiomyocytes.
pubmed:affiliation
Department of Cardiology and Pneumology, Georg-August-University Goettingen, Goettingen, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't