A. A. Soldatov¹, I. A. Parfyonova²

¹Institute of Biology of Southern Seas, National Academy of Science of Ukraine, Sevastopol;
e-mail: alekssoldatov@yandex.ru;
²Sevastopol National Technical University, Ukraine

Influence of temperature in the range of 1-15 °С on oxygen binding properties of blood of thermophilic – golden mullet (Liza aurata), anchovy (Engraulis encrasicolus), and cold-tolerant – sardelle (Clupeonella cultriventris) fishes has been investigated under experimental conditions. Heat dependence of oxygenation reaction in thermophilic fish blood at temperature below 10 °C considerably increases, which is evidenced by high ΔH values. That is accompanied by a substantial increase of blood oxygen affinity and complicates blood deoxygenation at the tissue level. This reac­tion is apparently determined by the change of hemoglobin interaction with intraerythrocyte medium. The concentration of NTP in erythrocytes increases, that partially compensates negative changes of blood oxygen affinity (parameter P₅₀ is raised) under long-term maintenance of fishes at 5 °С. However this reaction is not observed at low temperatures (1-2 °C).

Keywords: erythrocyte, hemoglobin, hypothermia, marine fishes, nucleotide triphosphate, oxy­gen affinity