Impairment of Barrier Properties of Erythrocyte Membranes Caused by Low Temperatures is a Result of Disorganization of Hemoglobin Supramolecular Structure

BACKGROUND: The antecedence of impairment of plasmatic membrane structure and functions forms the basis of the dominative concept about mechanisms of cell cryoinjuries. A role of alterations of hemoglobin supramolecular structure in erythrocytes remains unclear. OBJECTIVE: Comparison of continuity of membranes of native erythrocytes and resealed ghosts after freeze-thawing with a cryoprotectant at a low concentration (4%). MATERIALS AND METHODS: Cryoresistance of native erythrocytes and resealed ghosts with and without low concentrations of cryoprotectants (4% glycerol) was compared according to egress of the following markers: hemoglobin, ¹⁴C-sucrose and K⁺ as well as by scanning electron microscopy. RESULTS: It was found that resealed erythrocyte ghosts, where hemoglobin content was 4-5 times lower than in erythrocytes, were much more cryoresistant than native erythrocytes, which was especially noticeable when a low concentration of cryoprotectant (4% glycerol) was used. CONCLUSION: These data confirm an earlier proposed hypothesis on the role of supramolecular hemoglobin structure in cryoinjury mechanisms of erythrocytes.