Linked Life Data

14508241

Source:http://linkedlifedata.com/resource/pubmed/id/14508241

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2003-9-25
pubmed:abstractText
The authors examined effects of positive (dopamine and digoxin) and negative (nifedipine and lidocaine) inotropic interventions on the instantaneous cyclic relationship between myoplasmic [Ca2+] and simultaneously developed left ventricular pressure (LVP) in intact guinea pig hearts. Novel indices were developed to quantify this relationship based on (1) transient [Ca2+] and LVP signal morphology, ie, maxima and minima, peak derivatives, beat areas, durations, and ratios of indices of LVP to [Ca2+]; (2) temporal delay; and (3) LVP versus [Ca2+] loop morphology, ie, orientation, size, hysteresis, position, shape, and duration. These analyses were used to assess the cost of phasic [Ca2+] for contraction and relaxation over one beat after inotropic intervention. It was found that dopamine and digoxin increased contractile and relaxation responsiveness to phasic [Ca2+], cumulative Ca2+, and net Ca2+ flux. Unlike dopamine, digoxin did not decrease relaxation response time. Nifedipine and lidocaine decreased contractile and relaxation responsiveness to phasic [Ca2+], cumulative Ca2+, and net Ca2+ flux. Unlike lidocaine, nifedipine decreased net available Ca2+ and Ca2+ influx. Positive inotropic agents increased [Ca2+]-LVP loop area and hysteresis and resulted in a more vertically oriented loop. Nifedipine and lidocaine decreased these loop indices and lidocaine exhibited greater loop hysteresis than did nifedipine. These novel indices provide a quantitative assessment of myoplasmic [Ca2+] handling for cardiac contractile function.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0160-2446
pubmed:author
pubmed:issnType
Print
pubmed:volume
42
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
539-53
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
How inotropic drugs alter dynamic and static indices of cyclic myoplasmic [Ca2+] to contractility relationships in intact hearts.
pubmed:affiliation
Department of Biomedical Engineering, Marquette University, Milwaukee, Wisconsin, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S.