Dynamics of morphological and immunohistochemical changes in myocardium during hypothyroidism modeling in experiment

Abstract

An experimental model of hypothyroidism was obtained by thyroidectomy. The operation was carried out on 57 sexually mature male rats weighing 250–300 g. The experiment lasted 45 days. Laboratory animals were removed from the experiment on days 7th, 14th, 21st, 28th, 35th and 45th. As a control, 15 rats were used that were not operated on. For histological examination, pieces of rat myocardium were taken from the left and right ventricles. The pieces were fixed in 10% buffered formalin for 10 days. Histological sections were prepared in a standard manner. Sections were stained with hematoxylin and eosin, picrofuchsin according to van Gieson, toluidine blue, according to Mallory. Results of the study: In the myocardium of rats, hemodynamic disorders, edema, hydropic degeneration of cardiomyocytes, myocytolysis, fragmentation of muscle fibers, colliquation necrosis, compression and atrophy of muscle fibers were found. An immunohistochemical study revealed a decrease in the expression of desmin and sarcomeric actin.