AGE-RELATED CHANGES OF VASCULAR BED WITHIN THYMUS GLAND IN MORPHOLOGICAL COMPARATIVE RANGE OF VERTEBRATE ANIMALS (CHORDATA, VERTEBRATA)

Abstract

At present time, the issue of age-dependence of morphological parameters of the thymus blood vessels in members of various terrestrial vertebrates classes has been poorly studied, due to the lack of comparative morphological approaches. Therefore, the main goal of our work was to specify this kind of dependences. We studied samples of thymus glands from vertebrate animals belonging to four classes: Amphibians, Reptilian, Aves, and Mammals, including humans. For the first time, using methods of light microscopy, we performed comparative morphological studies of thymic blood microvessels in animals and humans, looking for age dependence of these differences. It was found the number and area of microcirculatory bed in thymic cortex and medullary substance depends on age, taxonomic class of the animal as well as on the environmental conditions. We have also revealed age-related differences of the intra-organ vasculature in thymus, including large arteries and venous vessels. Some specific age-related changes were found for human thymic vascular bed. On the basis of our studies, we can make conclusions about functional role of age-related changes of thymic blood vessels in immunity. The results of this study are important for basic and applied biology and medicine, being of interest to researches, especially in immunology.

Keywords

• thymus
• vertebrate animals
• correlation analysis
• age-related changes
• comparative morphology