[Morphologic and biochemical correlations in the muscle tissue of the atria and ventricles].

Electron microscope study of the heart muscle tissue demonstrated a difference between the cardiomyocytes of the auricles and ventricles. Three varieties of cells distinguished by the character of relations between the organoids and the number of specific secretory granules in them were revealed in the muscle tissue of the auricles. In studying the activity distribution of the lactate dehydrogenase (LDH) and its isoenzymatic pattern by disc electrophoresis and isoelectric focusing, the enzymatic spectra of LDH from the auricles and ventricles were found to differ considerably. It is suggested that the sources of energy and the mechanisms of energy production in the muscle cells of the auricles and ventricles are different.