Comparison of energy release in intact and skinned muscle fibres during development of isometric force

2002 ◽  
Vol 30 (1) ◽  
pp. A35-A35
Author(s):  
T.G. West ◽  
N.A. Curtin ◽  
M.A. Ferenczi ◽  
Z.-H. He ◽  
R.C. Woledge
Keyword(s):  
Energy Release ◽  
Isometric Force ◽  
Muscle Fibres ◽  
Skinned Muscle Fibres ◽  
Skinned Muscle

Thermal dependence of maximum Ca2+-activated force in skinned muscle fibres of the toad Bufo marinus acclimated at different temperatures

1987 ◽  
Vol 129 (1) ◽  
pp. 309-327
Author(s):  
B. B. Rees ◽  
D. G. Stephenson
Keyword(s):  
Isometric Force ◽  
Bufo Marinus ◽  
Muscle Fibres ◽  
Power Relationship ◽  
Force Output ◽  
Thermal Dependence ◽  
Skinned Muscle Fibres ◽  
Skinned Muscle ◽  
Different Temperatures ◽  
Residual Force

Mechanically skinned muscle fibres from the twitch region of the iliofibularis muscle of cool- (16 +/− 1 degree C) and warm- (32 +/− 1 degree C) acclimated cane toads (Bufo marinus) were activated maximally by Ca2+ in solutions of different pH and at different temperatures (approx. 1–35 degrees C). Acclimation of up to 12 weeks at 16 degrees C and up to 8 weeks at 32 degrees C did not modify the marked thermal dependence of isometric force in the skeletal muscle fibres of the cane toad. The prominent decline of maximum Ca2+-activated force at lower temperatures, a property which is not characteristic of muscles from other anurans, was associated with an obvious decline in fibre stiffness at temperatures below about 20 degrees C, regardless of the temperatures at which the toads were kept prior to experimentation. The results suggest that the decline of isometric force at lower temperatures is due both to a reduction in the number of cross-bridges and to a decrease in the force output per cross-bridge. The maximum Ca2+-activated force response increased when fibres were activated in solutions of increasing pH at all temperatures investigated. This trend is expected to have a compensatory effect on the thermal dependence of the maximum Ca2+-activated force under physiological conditions, because of the elevation of intracellular pH as temperature declines. The isometric force did not depend on the concentration of the zwitterionic species of the pH buffer in solutions. The skinned fibre preparation developed a Ca2+-insensitive residual force following maximal activation. The increment in residual force followed a linear relationship with the duration of activation at a given temperature and a power relationship of activation temperature for a given duration of activation. Fibres from warm-acclimated animals developed less residual force following activations at 15 degrees C than did fibres from cool-acclimated animals, suggesting that thermal acclimation may substantially reduce the magnitude of this phenomenon at temperatures below 20 degrees C.

scholarly journals Thin Filament Activation and Unloaded Shortening Velocity of Rabbit Skinned Muscle Fibres

2003 ◽  
Vol 550 (1) ◽  
pp. 205-215 ◽  
Author(s):  
Carl A. Morris ◽  
Larry S. Tobacman ◽  
Earl Homsher
Keyword(s):  
Thin Filament ◽  
Muscle Fibres ◽  
Shortening Velocity ◽  
Skinned Muscle Fibres ◽  
Skinned Muscle ◽  
Filament Activation

scholarly journals Effect of Active Shortening and Stretching on Lattice Spacing and Cross-Bridge Binding in Skinned Muscle Fibres

2016 ◽  
Vol 110 (3) ◽  
pp. 301a
Author(s):  
Venus Joumaa ◽  
Ian C. Smith ◽  
Tim R. Leonard ◽  
Olga Antipova ◽  
Thomas C. Irving ◽  
...  
Keyword(s):  
Lattice Spacing ◽  
Muscle Fibres ◽  
Cross Bridge ◽  
Skinned Muscle Fibres ◽  
Skinned Muscle
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