Morphofunctional characteristic of myocardium in experimental diabetes mellitus

Abstract

The main cause of death in patients with DM is damage of the cardiovascular system, in particular, the development of diabetic cardiomyopathy and the appearance of such serious complications, as myocardial infarction.
Purpose — to study the morphofunctional changes of cardiomyocytes and vessels of the hemomicrocirculatory blood flow of rats’ myocardium at histo- and ultrastructural levels in the late stages of streptozotocin diabetes mellitus.
Materials and methods. The material for the study were pieces of the ventricles of the myocardium of 10 male Wistar rats. Animals were divided into 2 groups: control and experimental. Diabetes mellitus was simulated by a single intraperitoneal injection of streptozotocin (6 mg per 100 g of body weight). The material was taken on the 56th day of the experiment. Histological, electron microscopic and statistical research methods were used.
Results. After 56 days of experimental DM, we note a decrease in the area of the cardiomyocyte profile by 7.9-13.6% compared with the control group of animals (in all cases p<0.05). We find an increase in the area of the wall profile and a decrease in the area of the lumen of arterioles and capillaries, which is accompanied by an increase in the Wogenworth index by 93.0% in arterioles and 57.3% in capillaries (in all cases p<0.05). In the latter we detect the proliferation of the basal membrane by individual plates. Such changes in the vessels of the hemomicrocirculatory blood flow indicate the development of diabetic microangiopathy.
Conclusions. In the late stages of experimental diabetes mellitus, we note pronounced signs of diabetic cardiomyopathy, which morphologically manifests itself in cardiomyocytes: a decrease in their area, destructive changes in mitochondria, defibrillation and focal lysis of myofibrils, subsarcolemic edema. Such changes are observed against the background of the development of diabetic microangiopathy.