Figure 4.

Histopathological analysis of the myocardium of animals belonging to different experimental groups. Representative photomicrographs of histopathological analyses of the rat myocardium from the SHAM, SS + CIR, MB + ISQ, and ISQ + MB groups. In the SHAM group, the myocardium is characterized by the absence of necrosis and striated cells with well-centralized nuclei of normal color and size. In the SS + CIR group, there is intense necrosis due to coagulation, with pyknotic cells (decentralized nuclei and condensation of the chromatin), a marked number of cells undergoing karyolysis (absence of nucleus and cytoplasmic eosinophilia), and swelling and vacuolization. In the MB + ISQ group, similarly, there is intense necrosis due to coagulation, with intense tissue loss, areas of myocytolysis, muscle fibers with swelling (increase in cell volume due to accumulation of water, due to ionic imbalance, reversible), vacuolation, and cells with reduced nuclei or in karyolysis. However, in the MB + ISQ group, the myocardium shows mild necrosis by coagulation, with mild, mild karyolysis, swelling, absence of vacuolization, and preservation of a large part of the striated cells (HE with 400× magnification).