[Erythrocytes of hetero- and homoiothermal animals in natural and artificial hypothermia].

By the low-angle light scattering technique there are revealed peculiarities of dynamics of transformation (osmotic fragility, level of hemolysis and ratio of forms by index of sphericity) of erythrocytes of hetero- (golden hamsters Mesocricetus auratus) and homoiothermal (white rats Rattus norbegicus) animals in natural hibernation and suspended animation, craniocerebral and immersion hypothermia. In control in hamsters the osmotic fragility and the level of hemolysis of erythrocytes were higher than in rats, predominant were modified forms (in particular stomatocytes). Under artificial hypothermia, regardless of the way of achievement, depth and duration, we observed changes similar in direction, but different in expression: the osmotic fragility and hemolysis increased, the portion of discocytes decreased (especially sharply in hamsters under suspended animation), the number of changed erythrocytic forms rose. In contrast, under hiberation the osmotic fragility, hemolysis and the amount of stomatocytes declined, the portion of discocytes increased, but at the same time the amount of prehemolytic forms (spherocytes) rose too. In 24 hs there occurred a decrease of osmotic fragility (after suspended animation more pronounced in hamsters) and the level of hemolysis (especially after immersion hypothermia), the portion of discocytes was restored, in hamsters after suspended animation and in rats after immersion hypothermia it even exceeded the control level; spherocytes in blood of hamsters were not revealed, in rats they were elevated. Possibly, the observed qualitative change of population of spherocytes 24 h after hypothermia toward its homogeneity is determined not only at the level of elimination of old and defected cells, activation of erythropoiesis, the appearance of highly resistant erythrocytes, but also at the level of time membrane-stabilizing mechanisms.