Ultrastructural study on the photoreceptor layer in streptozotocin-induced diabetic rats

The aim of this research was to investigate the ultrastructure of the photoreceptor layer of diabetic male Wistar rat retina. Ten apparently healthy Wistar adult rats (aged 75 days) were used and divided into two groups: (1) control group and (2) diabetic group (injected intraperitoneally with streptozotocin 90 mg/kg). Samples were taken as small pieces from the retina near the optic disc and studied using a transmission electron microscope. Results showed that outer segments loss, scattered inner segments, and condense and pyknotic nuclei and karyolysis were obvious in diabetic group. The quantitative evaluations of different layers of photoreceptor cells showed that a significant decrease was observed in outer segments, inner segments, and outer nuclear layers in diabetic group compared with control group. This study concluded that diabetes caused major signs of pathology in the ultrastructure of photoreceptor layer of the rat retina.