Structural features of the mesonephros of semianadromous fish on the example of the European smelt (Osmerus eperlanus)

At present, special attention is drawn to the study of adaptation aquatic organisms a complex environmental factors precisely at cellular level. It very important structural and functional features kidney, which not only plays key role in osmoregulation, but also makes significant contribution maintaining homeostasis level functioning single nonspecific defense system body. In this aspect, species belonging unique ancient group, united order salmoniformes, highly relevant. Using methods light electron microscopy, we investigated morphology ultrastructure mesonephros population semianadromous ecological form European smelt Osmerus eperlanus inhabiting Gulf Finland Baltic Sea performing spawning migrations Luga River Leningrad Region. The general scheme trunk kidney organization given, ratio leukocytes structures nephron are revealed. shown that development hematopoietic tissue mesonephros, number mature forms granulocytes systematic signs do depend on ecology species. leukocytes, width cisterns rough endoplasmic reticulum plasma cells, structure granules associated with peculiarities link immune under certain conditions habitat. ultrafine ion-transporting interstitial as well ultrastructural found nephron, can be considered cytological markers lifestyle.