Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1999-7-12
pubmed:abstractText
1. To assess the specific functions of the cardiac isoform of troponin I (cTnI), we produced transgenic mice that expressed slow skeletal troponin I (ssTnI) specifically in cardiomyocytes. Cardiomyocytes from these mice displayed quantitative replacement of cTnI with transgene-encoded ssTnI. 2. The ssTnI transgenic mice were viable and fertile and did not display increased mortality or detectable cardiovascular histopathology. They exhibited normal ventricular weights and heart rates. 3. Permeabilized transgenic cardiomyocytes demonstrated an increased Ca2+ sensitivity of tension and a lack of contractile responsiveness to cAMP-dependent protein kinase (PKA). Isolated cardiomyocytes from transgenic mice had normal velocities of unloaded shortening but unlike wild-type controls exhibited no enhancement of the velocity of shortening in response to treatment with isoprenaline. Transgenic cardiomyocytes exhibited greater extents of shortening than non-transgenic cardiomyocytes at baseline and after treatment with isoprenaline. 4. The rates of rise of intracellular [Ca2+] and the peak amplitudes of the intracellular [Ca2+] transients were similar in transgenic and wild-type myocytes. However, the half-time of intracellular [Ca2+] decay was significantly greater in the transgenic myocytes. This change in decay of intracellular [Ca2+] was correlated with an increase in the re-lengthening time of the transgenic cells. 5. These changes in cardiomyocyte function in vitro were manifested in vivo as impaired diastolic function both at baseline and after stimulation with isoprenaline. 6. Thus, cTnI has important roles in regulating the Ca2+ sensitivity of cardiac myofibrils and controlling cardiomyocyte relaxation and cardiac diastolic function. cTnI is also required for the normal responsiveness of cardiomyocytes to beta-adrenergic receptor stimulation.
pubmed:grant
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-1722208, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-1934363, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-1959627, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-2142896, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-2173135, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-2365354, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-2535795, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-2760067, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-2966401, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-3168178, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-372827, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-6131381, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-6211626, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-6217205, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-6287209, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-6547162, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-7053370, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-7473784, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-7577919, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-7601340, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-7641333, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-7701323, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-8031779, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-8062415, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-8118962, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-8144655, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-8160816, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-8415650, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-8435448, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-8477526, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-8530495, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-8530519, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-8618961, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-8760070, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-8777429, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-9038224, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-9144257, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-9241277, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-9341222, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-9637714, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-9734469, http://linkedlifedata.com/resource/pubmed/commentcorrection/10226156-9788962
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0022-3751
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
517 ( Pt 1)
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
143-57
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
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