[Thermohemolysis of erythrocytes in the temperature range including physiologic (autohemolysis)]

The activation energy of thermohemolysis of erythrocytes changes from 36 +/- 5 kcal/mol (35-45 degrees C) to 97 +/- 5 kcal/mol (45-55 degrees C) at the temperature about 45 degrees C in isotonic buffer. The break on Arhenius' plot is preserved also when erythrocytes are placed into plasma. The character of Arhenius' plot is the same when erythrocyte hemoglobin is totally oxidated into methemoglobin by chemical way, though thermal stability of such erythrocytes is decreased. The scheme is presented in which thermohemolysis of erythrocytes occurs by two independent ways: thermodenaturation of hemoglobin (limiting stage of the process when t greater than 45 degrees C) and modification of membrane proteins by hemin, the last being a product of hemoglobin oxidation (limiting stage of the process when t less than 45 degrees C).