MECHANISM OF CONTRACTION IN THE MUSCLE FIBER--ATP SYSTEM

The Signaling Mechanism of Contraction Induced by ATP and UTP in Feline Esophageal Smooth Muscle Cells

P2 receptors are membrane-bound receptors for extracellular nucleotides such as ATP and UTP. P2 receptors have been classified as ligand-gated ion channels or P2X receptors and G protein-coupled P2Y receptors. Recently, purinergic signaling has begun to attract attention as a potential therapeutic target for a variety of diseases especially associated with gastroenterology. This study determine...

Structural mechanism of muscle contraction.

X-ray crystallography shows the myosin cross-bridge to exist in two conformations, the beginning and end of the "power stroke." A long lever-arm undergoes a 60 degrees to 70 degrees rotation between the two states. This rotation is coupled with changes in the active site (OPEN to CLOSED) and phosphate release. Actin binding mediates the transition from CLOSED to OPEN. Kinetics shows that the bi...

The molecular mechanism of muscle contraction.

Computation of Muscle Fiber Contraction Dynamics.

This paper contains the modeling of muscle fiber contraction dynamics as a result of electrical stimulation. The novelty of the model is the possibility of running simultaneous analyses of the fiber’s action potential propagation and its biomechanical response. Simulations for different muscle fiber types, stimulus rates and contraction types can be run. The model correctly predicts the occurre...

Remarks on Muscle Contraction Mechanism

Muscle contraction mechanism is discussed by reforming the model described in an article by Mitsui (Adv. Biophys. 1999, 36, 107-158). A simple thermodynamic relationship is presented, which indicates that there is an inconsistency in the power stroke model or the swinging lever model. To avoid this difficulty, a new model is proposed. It is assumed that a myosin head forms a polaron-like comple...