[Excitation of the hydrogen bond by the energy of hydrolysis of adenosine-5'-triphosphate].

The model of muscle contraction suggested in [1] is based on the hypothesis that the first step of the conversion of chemical energy delta E (which is stored in adenosine-5'-triphosphate) is the excitation of the hydrogen bond in the actin-myosin system with a simultaneous hydrolysis of the adenosine-5'-triphosphate molecule. As a consequence, the potential barrier is decreased, and the break of the macroergic bond adenosine-5'-triphosphate-phosphate is facilitated. With the delta E value exceeding the excitation energy of the H-bond, this process represents an exothermic reaction.

[Statistics on actin globule chains, stretched by hydrogen bonds, and the Hill law in quantum mechanics theory of muscle contraction].

The process of sarcomere membranes approaching under the action of actin and myosin filament stretching is studied theoretically. In elaboration of previous studies it is supposed that this stretching is due to the formation of hydrogen bonds excited by the energy of ATP splitting. A possibility for the hydrogen bond breakage at different stages of contraction is considered to be the greater the more are the polymers stretched, and the larger statistical scatter in the moments of H-bonds formation at different filaments if it is supposed that sarcomere contraction occurs much slower than stretching of each separate filament.

[Cleavage time for a hydrogen bond under a load].

Statistics of the hydrogen bond formation and break in a bundle of actin and myosin filaments realizing the attractive force in the sarcomere of a muscle is studied. Purely mechanical problem of the attractive-force formation and motion of myosin heads and action globules under their action is supplemented by accounting for the irreversible processes: 1. Thermal de-excitation of the latter in the chain of hydrogen bond during the elementary act of the ATP energy use resulting in fixing the extended actin filament.

Excited hydrogen bonds in the molecular mechanism of muscle contraction.

The mechanism of muscle contraction is considered. The hydrolysis of an ATP molecule is assumed to produce the excitation of hydrogen bonds A--H..

[Myosin head swivel in a muscular contraction model based on an hypothesis on the role of hydrogen bond excitation].

A theory of muscle contraction developed by the authors in their earlier papers based on the idea of hydrogen-bond attractive force increase under excitation is modified for the model of myosin head swivel. The hydrogen bonds are supposed to be located at a hinge or near actin-myosin contact. The energy of ATP decay is transferred to the hydrogen bonds whose operation results in myosin head swivel.