Peculiarities of Morphological Changes of Endotheliocytes and Remodeling of the Arteries Under the Experimental Hypercholesterolemia

Abstract

Introduction: Under the conditions of experimental hypercholesterolemia, endothelial dysfunction develops with the morphological marker which is an increase in the number of blood-circulating desquamated endothelial cells (DEC), but this situation needs to be clarified in the development of this pathology in the age aspect. The aim: To find out the features of remodeling of endothelial cells and arteries of the hind limbs in the rats of pre-repopductive and reproductive age with experimental hypercholesterolemia. Materials and methods: The experimental group consisted of 16 animals with biochemically confirmed hypercholesterolemia, which were divided into 2 groups: group 1 – 8 animals, aged 2–3 months, weighing 150–170 grams and group 2 – 8 rats aged from 11 to 11 months weighing 230–250 gram. The control group consisted of rats of the same age of 8 animals in each. Results: Hypercholesterolemia causes damage to the vascular endothelium of the arteries, which is characterized by an increase in the number of desquamated endothelial cells in the peripheral blood. The most circulating blood in desquamated endothelial cells was detected in 45 days of study in animals of reproductive age, where the number of desquamated endothelial cells increased by 2.56 times, and in animals of pre-reproductive age – 2.35 times. Morphological changes were characterized by thickening of the intima of the arteries of the femur, knee and tibia due to swelling of the endothelial cells, their desquamation and proliferative changes in places of preserved vascular endothelium. In response to the deposition of lipids and PAS-positive substrates, cellular reactions appeared as weak lymphocytic infiltration. In addition to hyperlastosis, fragmentation of elastic fibers was revealed. Correlation of intima contributed to the narrowing of vascular lumen. Lipids, xanthoma cells and sour mucopolysaccharides were accumulated in the inner membrane of the arteries. In addition to lymphocytic infiltrates, the amount of collagen fibers in adventitia increased. Conclusions: Under conditions of hypercholesterolemia the number of desquamated endothelial cells in the blood increases, and arterial remodeling is characterized by manifestations of hypertrophic-neoplastic remodeling in rats of pre-reproductive age, and in reproductive animals there were sclerotic and inflammatory changes.