[The role of erythrocyte microvesiculation and hemoglobin glycation in hemorheological disordes during burn injury].

INTRODUCTION: Hemorheological disorders play an important part in pathogenesis of acute period of burn injury. This mechanism remains practically unstudied. Thus, unknown is the role of hemoglobin glycation and erythrocyte microvesiculation in the decrease in erythrocyte deformability after thermal trauma. METHODS: Research was performed on 30 blood samples of burn patients in the acute period and 40 blood samples of healthy donors. The number of erythrocyte-derived microvesicles was determined by flow cytometry and then standardized in the samples; the microvesicles were preliminarily separated by ultracentrifugation at 100,000 g, for 60 minutes. Electrophoretic mobility of erythrocytes was measured in a processing chamber of the optical cuvette under the light microscope. Deformability of erythrocytes was assessed by the level of their extension in the artificial shear flow. RESULTS: It was found that the amount of HbA1c in red blood cells of burn patients demonstrated a 2-fold increase compared to healthy donors. In the experiments in vitro it was proved that deformability of erythrocytes correlates with the level of hemoglobin glycation. Hb glycation leads to the increased rigidity of erythrocytes also by increasing their microvesiculation. The number of microvesicles derived from red blood cells of burn patients demonstrated a 3.47-fold increase compared to healthy donors. An important reason for microvesiculation is the destabilization of lipid complex of erythrocyte membrane, which is accompanied by the increase in the erythrocyte negative charge. It can be concluded that Hb glycation and redistribution of erythrocyte membrane phospholipids are he important reasons for the increase erythrocyte microvesiculation and are accompanied by the decrease in erythrocyte deformability after thermal trauma.

The role of fibrinogen in aggregation of platelets in burn injury.

Spontaneous aggregation of platelets is considerably enhanced in the acute period after burn. The changes in indices-induced aggregation of platelets are non-uniform and not significant statistically. Thermal trauma is accompanied by the development of hyperfibrinogenemia and an increase in the level of oxidised fibrinogen. We studied the influence of fibrinogen concentration and the degree of its oxidation on aggregation of platelets. It was shown that the level of aggregation of platelets greatly depends on the concentration of fibrinogen (non-oxidised and oxidised) plasma. The possible mechanisms of these effects are investigated.