ANALYSIS OF SEASONAL DYNAMICS OF CAPILLARY EXCHANGE OF BLOOD SERUM PROTEINS OF GOLDFISHCARASSIUS AURATUS (L.)

The study of the patterns of blood serum proteins capillary exchange (CE) as a factor regulating water and osmotic homeostasis in the fish organism has been started using the example of goldfish Carassius auratus (L.). The analysis of the seasonal dynamics of the barrier properties of the muscle-type capillary wall to the blood serum protein has been carried out using the coefficient of the reflectance of total protein from the capillary wall (CW). The maximum values of the coefficient are calculated for spring, the minimum ones for summer, and the intermediate value for autumn. Such dynamics assume the most pronounced barrier function of the CW in spring and autumn, and the minimum one in summer during the period of preparation for spawning. The reason for this is a significant summer increase in the concentration of total protein in the interstitium of fish to a level comparable to that of blood serum and higher. This circumstance does not allow us to explain the seasonal dynamics of fish plasma protein capillary exchange within the framework of the classical Starling hypothesis, but fits well into the format of the albumin-free CE model developed for fish [Andreeva, 2020]. This model characterizes a decrease in the barrier function of CW as an adaptation for equalizing the osmolality of the body's internal fluids during the preparation of fish for spawning, which is characterized by high intensity of all metabolic processes.