The Relationship of Gametes and Somatic Cells of Male Gonads of Vertebrates: Evolutionary, Age and Seasonal Aspects, Adaptive and Reactive Transformations Under the Action of Destabilizing Factors

Abstract

The aim of the study is a comparative analysis of the morphofunctional interactions of germ and somatic cells in the organs of the male reproductive system of vertebrates during ontogenesis, under conditions of changes in reproductive activity and under the influence of destabilizing factors. Material and methods. Using light and electron microscopy, immunohistochemistry and morphometry, the testes of representatives of various classes of vertebrates (amphibians, reptiles, birds and mammals) were studied. The collection of material was carried out in environmentally safe ecosystems and in ecosystems with high anthropogenic load in the Orenburg region of Russia and in the Aktobe region of the Republic of Kazakhstan. Results. Based on the material of our own studies of the gonads, as well as on the basis of information from modern domestic and foreign literature, the patterns of relationships between germ cells and somatic cells of their microenvironment in the testes of vertebrates are shown. The features of the structural organization of the germinal and endocrine components of the male gonads are considered. The features of the structural organization of intertitial endocrinocytes (Leydig cells) are shown, and their high resistance to the action of various destabilizing factors compared to spermatogenic epithelium is established. Pubertal generation of endocrinocytes in vertebrate testes during reproductive age is characterized by stability in cell numbers and belongs to cell populations of a stable type. The role and significance of the structures of the blood-testis barrier are shown and the morphological equivalents of changes in the permeability of this barrier are established; it is revealed that in the studied animals, under the influence of negative anthropogenic factors, the integrity of the blood-testis barrier in the testes is violated. The action of destabilizing factors leads to a decrease in the number of developing germ cells in the lumen of the epididymal tubules (up to their complete disappearance in individual individuals), which is probably due to the deterioration of the trophic influences on them from the structures of the epididymis. Conclusion. The principle of organization of the main compartments of the testes, the convoluted seminiferous tubules and the interstitium of the organ, formed during evolution, probably turned out to be evolutionarily advantageous, since it is represented in the testes of all amniotes - reptiles, birds and mammals. In the process of evolutionary development, several types of structural organization of convoluted seminiferous tubules and interstitium were formed in the testes of vertebrates. The need to protect developing germ cells from the effects of immunocytes, which led to the formation of a blood-testis barrier in the testes.