| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Biophys J, October 2002, p. 2152-2161, Vol. 83, No. 4
Institute of Physiology, University Cologne, D-50931 Köln, Germany
Kinetics of force development and relaxation after rapid
application and removal of Ca2+ were measured by atomic
force cantilevers on subcellular bundles of myofibrils prepared from
guinea pig left ventricles. Changes in the structure of individual
sarcomeres were simultaneously recorded by video microscopy. Upon
Ca2+ application, force developed with an exponential rate
constant kACT almost identical to
kTR, the rate constant of force
redevelopment measured during steady-state Ca2+ activation;
this indicates that kACT reflects isometric
cross-bridge turnover kinetics. The kinetics of force relaxation after
sudden Ca2+ removal were markedly biphasic. An initial slow
linear decline (rate constant kLIN) lasting
for a time tLIN was abruptly followed by an
~20 times faster exponential decay (rate constant
kREL). kLIN is
similar to kTR measured at low activating
[Ca2+], indicating that kLIN
reflects isometric cross-bridge turnover kinetics under relaxed-like
conditions (see also Tesi et al., 2002. Biophys. J. 83:2142-2151). Video microscopy revealed the following: invariably at
tLIN a single sarcomere suddenly lengthened and returned to a relaxed-type structure. Originating from this sarcomere, structural relaxation propagated from one sarcomere to the
next. Propagated sarcomeric relaxation, along with effects of stretch
and Pi on relaxation kinetics, supports an intersarcomeric chemomechanical coupling mechanism for rapid striated muscle relaxation in which cross-bridges conserve chemical energy by strain-induced rebinding of Pi.
Biophys J, October 2002, p. 2152-2161, Vol. 83, No. 4
© 2002 by the Biophysical Society 0006-3495/02/10/2152/10 $2.00
This article has been cited by other articles:
 |
|
 |
|
  J. J. Rice, F. Wang, D. M. Bers, and P. P. de Tombe Approximate Model of Cooperative Activation and Crossbridge Cycling in Cardiac Muscle Using Ordinary Differential Equations Biophys. J., September 1, 2008; 95(5): 2368 - 2390. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. L. Kreutziger, N. Piroddi, B. Scellini, C. Tesi, C. Poggesi, and M. Regnier Thin filament Ca2+ binding properties and regulatory unit interactions alter kinetics of tension development and relaxation in rabbit skeletal muscle J. Physiol., August 1, 2008; 586(15): 3683 - 3700. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. Tachampa, T. Kobayashi, H. Wang, A. F. Martin, B. J. Biesiadecki, R. J. Solaro, and P. P. de Tombe Increased Cross-bridge Cycling Kinetics after Exchange of C-terminal Truncated Troponin I in Skinned Rat Cardiac Muscle J. Biol. Chem., May 30, 2008; 283(22): 15114 - 15121. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. P. Davis and S. B. Tikunova Ca2+ exchange with troponin C and cardiac muscle dynamics Cardiovasc Res, March 1, 2008; 77(4): 619 - 626. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. Iorga, N. Blaudeck, J. Solzin, A. Neulen, I. Stehle, A. J. L. Davila, G. Pfitzer, and R. Stehle Lys184 deletion in troponin I impairs relaxation kinetics and induces hypercontractility in murine cardiac myofibrils Cardiovasc Res, March 1, 2008; 77(4): 676 - 686. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Solzin, B. Iorga, E. Sierakowski, D. P. Gomez Alcazar, D. F. Ruess, T. Kubacki, S. Zittrich, N. Blaudeck, G. Pfitzer, and R. Stehle Kinetic Mechanism of the Ca2+-Dependent Switch-On and Switch-Off of Cardiac Troponin in Myofibrils Biophys. J., December 1, 2007; 93(11): 3917 - 3931. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. Todd, J. L. Taylor, J. E. Butler, P. G. Martin, R. B. Gorman, and S. C. Gandevia Use of motor cortex stimulation to measure simultaneously the changes in dynamic muscle properties and voluntary activation in human muscles J Appl Physiol, May 1, 2007; 102(5): 1756 - 1766. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
I. A. Telley, E. Stussi, J. Denoth, R. Stehle, G. Pfitzer, and K. W. Ranatunga Reply from I. A. Telley, R. Stehle, K. W. Ranatunga, G. Pfitzer, E. Stussi and J. Denoth J. Physiol., July 15, 2006; 574(2): 629 - 630. [Full Text] [PDF]
|
|
|
|
|
|
S. A. Niederer, P. J. Hunter, and N. P. Smith A Quantitative Analysis of Cardiac Myocyte Relaxation: A Simulation Study Biophys. J., March 1, 2006; 90(5): 1697 - 1722. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
I. A. Telley, J. Denoth, E. Stussi, G. Pfitzer, and R. Stehle Half-Sarcomere Dynamics in Myofibrils during Activation and Relaxation Studied by Tracking Fluorescent Markers Biophys. J., January 15, 2006; 90(2): 514 - 530. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M Kruger, S Zittrich, C Redwood, N Blaudeck, J James, J Robbins, G Pfitzer, and R Stehle Effects of the mutation R145G in human cardiac troponin I on the kinetics of the contraction-relaxation cycle in isolated cardiac myofibrils J. Physiol., April 15, 2005; 564(2): 347 - 357. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Martin, M. G. Bell, G. C. R. Ellis-Davies, and R. J. Barsotti Activation Kinetics of Skinned Cardiac Muscle by Laser Photolysis of Nitrophenyl-EGTA Biophys. J., February 1, 2004; 86(2): 978 - 990. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Tesi, N. Piroddi, F. Colomo, and C. Poggesi Relaxation Kinetics Following Sudden Ca2+ Reduction in Single Myofibrils from Skeletal Muscle Biophys. J., October 1, 2002; 83(4): 2142 - 2151. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
