Differential scanning microcalorimetry was used to show a destabilizin
g effect of ethanol on erythrocyte membrane proteins. The thermostabil
ity of the membrane cooperative unit, with the main protein being band
3 integral protein, was decreased most significantly, which was proba
bly related to a disturbance in protein - lipid complementary. At suff
iciently high ethanol concentrations the denaturational changes in the
membrane proteins resulted in lysis of red blood cells preceeding at
several stages: morphological changes in cells, as well as swelling an
d the lysis, proper. The activation energy of the ethanol-induced lysi
s as determined from the temperature dependence of the apparent hemoly
sis rate constant was equal to 150+/-20 kJmol-1 at 5,1 M ethanol conce
ntration. This corresponded to the activation energy of the protein de
naturation.