The condition of the conjunctival vessels of the rat eye in the subchronic and chronic periods of experimental streptozotocin diabetes

Authors

DOI:

https://doi.org/10.26641/1997-9665.2024.2.78-83

Keywords:

eye, conjunctiva, hemomicrocirculatory bed, capillary, angiopathy, experiment, diabetes, rat.

Abstract

Background. Diabetes mellitus is a significant medical and social issue. This is due to the challenges in early diagnosis, its widespread prevalence, and the severity of its complications, despite advancements in treatment. Despite the widespread adoption of cutting-edge diagnostic and therapeutic technologies, diabetic retinopathy remains a leading cause of vision impairment among the working population. Even today, eye complications from diabetes pose a substantial medical and social challenge worldwide. The aim of our study was to investigate the features of the conjunctival hemomicrocirculatory bed in rats during subchronic and chronic periods of experimental streptozotocin-induced diabetes mellitus. Methods. The study was conducted on 25 adult, non-pedigree white male rats weighing 120-130 g. The work used 2 groups of animals: group 1 (10 animals) with developing diabetes mellitus (2 weeks after streptozotocin administration); group 2 (10 animals) with established diabetes mellitus (6 weeks after streptozotocin administration); group 3 was a control group (5 animals) that received injections of 0.9% saline solution for 6 weeks. Microscopic studies and photographing of the preparations were performed using a MBI-1 microscope and a Nicon D 3100 digital camera. Results. Our studies showed that the capillary network is denser in the area of the lower transitional fold of the conjunctiva of the rat eyeball. Visually, individual capillaries with a linear direction of location are observed, or separate areas of the capillary network in the form of one or several loops. Quite often, the loops of the capillary network of the conjunctiva have a polygonal shape. In patients with experimental diabetes induced by streptozotocin, characteristic manifestations in the conjunctiva include the appearance of capillary microaneurysms, predominantly in the venous bend, the appearance of tortuosity, a decrease in the density of the capillary network, and, as a consequence, obliteration of part of the capillaries. It can be clearly stated that diabetes is associated with a decrease in the lumen of the capillaries. This study will provide a pathomorphological basis for establishing optimal timeframes, from the perspective of experimental morphology, for future pharmacologic correction of changes in the vascular structures of the rat eyeball during subchronic and chronic periods. This is crucial for stabilizing the emerging and progressively worsening manifestations of diabetic microangiopathy.

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Published

2024-07-30

How to Cite

Rudnytska , K., Pankevych , L., Kaminska, M., Poliiants , A., & Tverdokhlib , I. (2024). The condition of the conjunctival vessels of the rat eye in the subchronic and chronic periods of experimental streptozotocin diabetes. Морфологія / Morphologia / Morfologìâ, 18(2), 78–83. https://doi.org/10.26641/1997-9665.2024.2.78-83

Issue

Vol. 18 No. 2 (2024)

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Статті

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