FEATURES OF ULTRASTRUCTURAL CHANGES IN THE NEUROSENSORY ELEMENTS OF THE RETINA OF RATS IN THE MODELING OF DIABETIC RETINOPATHY ON THE BACKGROUND OF AXIAL MYOPIA

Abstract

The formation and development of diabetic retinopathy in conditions of myopization of the eyeball is accompanied by the features of the clinical picture of retinopathy. With myopia, the incidence of especially proliferative retinopathy, as well as the rate of progression of these diabetic changes in the retina, can be reduced. The aim of our work was a comparative study of the ultrastructure of the neurosensory elements of the retina in rats in the simulation of streptozotocin-induced diabetes and deprivation axial myopia. Experiments were performed on rats aged from 2 to 10 weeks, which were divided into 4 groups. The 1st control group included intact animals, the 2nd - with myopia, the 3rd - with diabetes; the 4th - with myopia and diabetes. Two-week-old rats were modeled with a high degree of axial myopia by blepharorrhaphy of both eyes and exposure to low light for another 2 weeks. In rats with axial myopia and intact rats, streptozotocin-induced diabetes was modeled by repeated intraperitoneal administration of subdiabetic doses of streptozotocin (15.0 mg/kg body weight) for 5 days. After 2 months, all animals were removed from the experiment under anesthesia and their eyes were enucleated. The tissue samples were photographed in a PEM-100-01 electron microscope and the ultrastructure of the neurosensory elements of the retina was studied. The obtained results of the study indicate that ultrastructural retinal neurosensory elements differed in different groups. When modeling diabetes against the background of axial myopia, some areas with signs of hydropic dystrophy with large fields of organelle destruction were observed in the cells of the inner layers of the retina, mainly in the inner nuclear layer, which is inherent in diabetes, but there were also areas whose ultrastructure was close to normal. This indicates that the process of myopization of the eyeball of rats with the lengthening of the anterior-posterior axis can mitigate the severity of ultrastructural changes of the retina in the simulation of diabetic retinopathy.