Staurosporine Inhibits Frequency-Dependent Myofilament Desensitization in Intact Rabbit Cardiac Trabeculae
Joint Authors
Janssen, Paul M. L.
Davis, Jonathan P.
Varian, Kenneth D.
Biesiadecki, Brandon J.
Ziolo, Mark T.
Source
Biochemistry Research International
Issue
Vol. 2012, Issue 2012 (31 Dec. 2012), pp.1-10, 10 p.
Publisher
Hindawi Publishing Corporation
Publication Date
2012-05-09
Country of Publication
Egypt
No. of Pages
10
Main Subjects
Topics
Abstract EN
Myofilament calcium sensitivity decreases with frequency in intact healthy rabbit trabeculae and associates with Troponin I and Myosin light chain-2 phosphorylation.
We here tested whether serine-threonine kinase activity is primarily responsible for this frequency-dependent modulations of myofilament calcium sensitivity.
Right ventricular trabeculae were isolated from New Zealand White rabbit hearts and iontophoretically loaded with bis-fura-2.
Twitch force-calcium relationships and steady state force-calcium relationships were measured at frequencies of 1 and 4 Hz at 37 °C.
Staurosporine (100 nM), a nonspecific serine-threonine kinase inhibitor, or vehicle (DMSO) was included in the superfusion solution before and during the contractures.
Staurosporine had no frequency-dependent effect on force development, kinetics, calcium transient amplitude, or rate of calcium transient decline.
The shift in the pCa50 of the force-calcium relationship was significant from 6.05±0.04 at 1 Hz versus 5.88±0.06 at 4 Hz under control conditions (vehicle, P<0.001) but not in presence of staurosporine (5.89±0.08 at 1 Hz versus 5.94±0.07 at 4 Hz, P=NS).
Phosphoprotein analysis (Pro-Q Diamond stain) confirmed that staurosporine significantly blunted the frequency-dependent phosphorylation at Troponin I and Myosin light chain-2.
We conclude that frequency-dependent modulation of calcium sensitivity is mediated through a kinase-specific effect involving phosphorylation of myofilament proteins.
American Psychological Association (APA)
Varian, Kenneth D.& Biesiadecki, Brandon J.& Ziolo, Mark T.& Davis, Jonathan P.& Janssen, Paul M. L.. 2012. Staurosporine Inhibits Frequency-Dependent Myofilament Desensitization in Intact Rabbit Cardiac Trabeculae. Biochemistry Research International،Vol. 2012, no. 2012, pp.1-10.
https://search.emarefa.net/detail/BIM-460822
Modern Language Association (MLA)
Varian, Kenneth D.…[et al.]. Staurosporine Inhibits Frequency-Dependent Myofilament Desensitization in Intact Rabbit Cardiac Trabeculae. Biochemistry Research International No. 2012 (2012), pp.1-10.
https://search.emarefa.net/detail/BIM-460822
American Medical Association (AMA)
Varian, Kenneth D.& Biesiadecki, Brandon J.& Ziolo, Mark T.& Davis, Jonathan P.& Janssen, Paul M. L.. Staurosporine Inhibits Frequency-Dependent Myofilament Desensitization in Intact Rabbit Cardiac Trabeculae. Biochemistry Research International. 2012. Vol. 2012, no. 2012, pp.1-10.
https://search.emarefa.net/detail/BIM-460822
Data Type
Journal Articles
Language
English
Notes
Includes bibliographical references
Record ID
BIM-460822