Morphological And Morphometric Characteristics Of Rat Thymus During Experimental Intestinal Cicatricial Process

Abstract

The intestinal cicatricial process is accompanied by the development of systemic morphofunctional changes affecting the central organs of immunogenesis; however, the features of age-related timus restructuring in this pathology have not been sufficiently studied. The aim of the study is to study the morphological and morphometric features of the thymus of white purebred rats of various ages during the experimental intestinal cicatricial process. Materials and methods. The study was conducted on white purebred rats aged 4, 7, and 10 months. The intestinal cicatricial process was experimentally modeled, after which histological and morphometric studies of the thymus were conducted. The histological specimens were stained with hematoxylin and eozine. The architectonics of the thymus lobes, the state of the cortical and medullary substance, cell density, vascular bed features, and the organ's main morphometric indicators were evaluated. The obtained results were subjected to statistical processing. Results. It was established that in the control group of 4-month-old animals, the thymus is characterized by a well-defined cortical substance with a high density of lymphoid cells, which corresponds to the period of active functional formation of the immune system. During the experimental intestinal cicatricial process in all age groups, structural disorders of the thymus were identified, manifesting as a decrease in cortical substance thickness, a decrease in thymocyte density, a relative increase in medullary substance, vascular disorders, and signs of involuntary changes. The severity of morphological and morphometric changes increased with age, indicating a decrease in the compensatory capabilities of the thymus. Conclusion. The experimental intestinal cicatricial process causes a pronounced age-dependent structural restructuring of the thymus, accompanied by changes in its morphometric parameters and signs of decreased functional activity. The obtained data expand the understanding of the mechanisms of damage to the central organs of immunogenesis in chronic intestinal pathology and can serve as a basis for developing immunocorrective therapy methods.

Keywords:

Thymus, intestinal cicatricial process, rats

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