The Resistance of Erythrocytes in Some Black Sea Hyposmic Fishes Exposed to the Nonionic Detergents Triton X-100 and Tween-20.

Abstract—The osmotic resistance of erythrocytes and the hemolytic effect of nonionic detergents, Triton X‑100 and Tween-20, on red blood cells were analyzed in four hyposmiс Black Sea fish species: horse mackerel (Trachurus mediterraneus ponticus Aleev), gilthead (Diplodus annularis L.), black scorpionfish (Scorpaena porcus L.) and thornback ray (Raja clavata L.). It was revealed that in physiological solutions, red blood cells from hyposmic thornback ray and black scorpionfish were highly resistant to a hypotonic environment. By determination of the concentration of physiological solution in which 50% of fish erythrocytes (C_50%) were hemolyzed during incubation it was possible to rank fish erythrocytes according to the degree of osmotic resistance in the following order: black scorpionfish > thornback ray > gilthead > horse mackerel. The erythrocytes of the investigated teleost fishes exhibited a clear dependence on the mobility by C_50%, which increased in some fish with a decrease in their motor activity. Triton X-100 did not induce an increase in resistance or even weakly stimulated an increase in the hemolytic activity of erythrocytes in gilthead and thornback ray. In the presence of Triton X-100 in horse mackerel erythrocytes, cell resistance increased by a factor of 4.7 in an incubation medium with 50% dilution. Protective properties of Triton X-100 were seen during incubation of black scorpionfish erythrocytes in media with 70% dilution. Tween-20 also increased the resistance of fish erythrocytes to hemolysis. The results of this study demonstrated that Tween-20 and, in some cases, Triton X-100, are useful in maintaining stability of fish erythrocyte suspensions during experimental studies. [ABSTRACT FROM AUTHOR]