Changes in Morphometric Indicators of Blood Vessels of Masticatory Muscles in Simulation of Diabetic Angiopathy in Rats

Abstract

Summary. Relevance. Diabetic joint damage is common in the clinic. The blood vessels of the masticatory muscles that affect the morphogenesis of diabetic arthropathy of the temporomandibular joint remain poorly studied in this pathology. Objective: to study the features of remodeling of blood vessels of the masticatory muscles of the temporomandibular joint in experimental hyperglycemia by quantitative morphological methods. Materials and Methods. The study material was 45 laboratory mature white male rats, which were divided into 3 groups. The 1st group consisted of 15 intact apparently healthy animals, the 2nd included 15 rats with one-month diabetic angiopathy, and the 3rd had 15 rats with two-month specified pathology. Diabetes mellitus was simulated by a single intraperitoneal injection of streptozotocin from Sigma at a dose of 50 mg/kg. Euthanasia of animals was performed by bloodletting under thiopental anesthesia one and two months after the start of the experiment. The blood glucose concentration was determined. Histological micropreparations were made from the temporomandibular joint and the temporal and external pterygoid muscles. Morphometric measurements of small caliber arteries (outer diameter 26-50 μm), veins and microvessels of the hemomicrocirculatory tract were performed on muscle micropreparations; relative volumes of damaged synoviocytes and chondrocytes were determined on micropreparations of joints. Quantitative indicators were processed statistically. Results and Conclusions. It was revealed that the gleam of arteries considerably decreases, their wall thickens, and endotheliocytes are damaged in the studied muscles with the modeled pathology. Venous vessels are dilated, full-blooded with a reduced wall thickness. The most pronounced changes in these experimental conditions are the structure of microvessels, which is characterized by narrowing of arterioles, precapillary arterioles and hemocapillaries, pronounced expansion of postcapillary venules and venules. Plethora, stasis, thrombosis, irregularity of the lumen, sacculation, and varicose expansions were noted in venous microvessels. Venous fullness led to hypoxia, disorders of trophism and metabolism, dystrophy, necrobiosis of muscle fibers and stromal structures, foci of infiltration and sclerosis. It was revealed that morphological changes in the vascular bed of the masticatory muscles affect the morphogenesis of diabetic arthropathy of the temporomandibular joint.