Physics of muscle contraction

Mysteries of muscle contraction.

According to the cross-bridge theory, the steady-state isometric force of a muscle is given by the amount of actin-myosin filament overlap. However, it has been known for more than half a century that steady-state forces depend crucially on contractile history. Here, we examine history-dependent steady-state force production in view of the cross-bridge theory, available experimental evidence, a...

Water and Muscle Contraction

The interaction between water and the protein of the contractile machinery as well as the tendency of these proteins to form geometrically ordered structures provide a link between water and muscle contraction. Protein osmotic pressure is strictly related to the chemical potential of the contractile proteins, to the stiffness of muscle structures and to the viscosity of the sliding of the thin ...

Considerations on muscle contraction.

The independent force generator and the power-stroke cross-bridge model have dominated the thinking on mechanisms of muscular contraction for nearly the past five decades. Here, we review the evolution of the cross-bridge theory from its origins as a two-state model to the current thinking of a multi-state mechanical model that is tightly coupled with the hydrolysis of ATP. Finally, we emphasiz...

VIII. Properties of Muscle Contraction

Dynamics of smooth muscle contraction

Photolysis of caged calcium (Nitr5, Calbiochem®) can be used to studycalcium dependent processes such as excitation-contraction coupling andmuscular mechanics. Expensive high energy light sources are routinely used forUV light exposure; this study describes an alternative low cost Xenon flash unitconstmcted in our laboratOlY. A 300 J short arc Xenon flash lamp (Heimarl1l®)wa...