MORPHOMETRIC ASPECTS OF STUDY OF FEATURES OF REMODELING OF MICROVESSELS OF SYNOVIAL MEMBRANE OF THE KNEE JOINT AT DIABETIC ARTHROPATHY

Abstract

Joint damage in patients with diabetes is a fairly frequent complication. Features of structural changes of blood vessels of the hemomicrocirculatory bed of synovial membranes at diabetic arthropathy have not been sufficiently investigated. The purpose of research – morphometric study of the features of remodeling of microvessels of the synovial membrane at experimental diabetic arthropathy of the knee joint. Methods and Material. The microvessels of the synovial membrane of the knee joint of 60 laboratory sexually mature white male rats, which were divided into 3 groups, were investigated using a complex of morphological methods. The 1 group included 20 intact animals, the 2 – 20 rats with one-month diabetic arthropathy of the knee joint, the 3 – 20 experimental animals with the two-month indicated pathology. Diabetes mellitus was simulated by a single intraperitoneal injection of streptozotocin by Sigma at a dose of 50 mg/kg. One month and two months after the start of the experiment, rats were euthanized by bloodletting under thiopental anesthesia. The vessels of the hemomicrocirculatory bed of the synovial membrane were studied by the non-injection method of impregnation with silver nitrate. The diameters of arterioles, precapillary arterioles, hemocapillaries, postcapillary venules, venules, and the density of microvessels per 1 mm² of tissue were determined on micropreparations in the synovial membrane. Quantitative indicators were processed statistically. Results and Discussion. Diabetic arthropathy led to pronounced remodeling of microvessels, which was characterized by narrowing of arterioles, precapillary arterioles, hemocapillaries and significant expansion of postcapillary venules and venules, which led to venous congestion and venous stasis. The density of microvessels per 1 mm² of tissue of the synovial membrane of the knee joint was lower by 15.7% during one-month experimental hyperglycemia, and by 18.8% during two-month hyperglycemia (p<0.001). A pronounced decrease of the density of microvessels indicated the deterioration of hemomicrocirculation, transcapillary exchange and trophicity of the studied structures. Optically, postcapillary venules and venules are markedly expanded, filled with blood, with foci of stasis, thrombosis, and diapedesis hemorrhages. Some of the hemocapillaries were reduced, they were visualized in the form of thick-walled fibrous formations with signs of hyalinosis, their total or incomplete obliteration of the lumens was also noted. Stromal and paravasal edema, foci of dystrophy and necrobiosis of epitheliocytes, endotheliocytes, and foci of sclerosis infiltration were observed in the conditions of simulated pathology. Identified pathohistological changes dominated in two-month diabetic arthropathy of the knee joint.

Keywords

• knee joint,diabetic arthropathy,microvessels,synovial membrane.