[Interpretation of the diffraction picture of a skeletal muscle during the active phase of contraction].

New data concerning changes in the diffraction patterns at muscle activation, obtained by X-ray studies with a high resolution rate helped to interpret the diffraction patterns of the skeletal muscle in the active phase of contraction. Changes in the intensity of the meridianal reflex 143 A at the time of isomeric contractions and during rapid mechanical muscle stimulus are discussed. Experimental data analysis and calculations of the diffraction pattern, corresponding to the states of rest and contraction, showed, that the observed changes can be explained by the model of contactless interaction of myosin bridges with fine fibers. The diffraction pattern at the active phase of contraction showed that the bridges are near the fine fiber, but are not attached to the specific centers of binding on the actin globules.