[Ultrastructural analysis of reactive changes in the myocardium upon embryo exposure to an alkylating agent]

Subcellular reaction of certain structural components in the chick embryo myocardium to a single dose of the alkylating cyclophosphamide compound has been studied electron microscopically. It has been stated that the muscle cell edema, desorganization of the intracellular organells, reactions of the lysosomal apparatus occur in the myocardium. Two types of the cardiac muscle cell edema are revealed: 1) without any disturbance in intracellular organells; 2) with their advanced desorganization. Cells in the capillary endothelium are affected simultaneously to the muscle cells of the myocardium. Regenerative processes result in normalization of ultramicroscopical structure of the muscle cells. The subcellular reaction of the embryonal myocardium is characterized by a rapid course of the destructive and regenerative processes.