Changes in the level of protein oxidative modification products in blood serum of different types of sturgeon in response to their adaptation to hyperosmotic environment

The article investigates changes in the level of oxidative proteins in the blood serum of sturgeons from different ecological and physiological groups in response to their adaptation to sea water. The study aim to identify physiological and biochemical differences in osmotic and ion regulation in different groups of sturgeons. Among the studied groups are sterlet Acipenser ruthenus Linnaeus, 1758 (freshwater species from the Middle Volga, migrating only within the river), Siberian sturgeon from the Lena river A. baerii Brandt, 1869 (freshwater species, making short-term food migration to the estuary with salinity of water up to 10 ‰), Russian sturgeon A. gueldenstaedtii Brandt et Ratzeburg, 1833 and Beluga Huso huso (Linnaeus, 1758) (brackish water anadromous species of the Volga-Caspian basin, making regular migration ‘river-sea-river’ and living in the Caspian waters with salinity up to 12–14 ‰). The carbonyl derivatives of proteins were identified in the blood serum using the method described in (Аrutyunyan el al. 2000). It is shown that in salty environment the level of oxidative proteins falls, in sterlet, remains unchanged in Siberian sturgeon, while in the studied anadromous species the fluctuations of oxidative proteins level match the dynamics of osmolarity — it increases within 12 hours after the transfer of fish into artificial sea water and decreases after the transition to the hypoosmotic type of regulation. It can be concluded that oxidative modification of serum protein is a significant marker of adaption in sturgeons of different ecological groups.