Осмотическая чувствительность эритроцитов млекопитающих при модификации их исходного состояния

Abstract

В работе исследовали влияние исходного состояния эритроцитов млекопитающих, сформированного под действием частичного обезвоживания, на их чувствительность к гипертоническому шоку (4,0 моль/л NaCl). В работе было показано, что максимально устойчивое состояния эритроцитов крысы, человека и лошади к гипертоническому шоку формируется в условиях предварительного инкубирования клеток как в солевых, так и в сахарозных средах, осмоляльность которых составляет – 400-800 мосм/кг, 700-800 мосм/кг и 600-800 мосм/кг, соответственно. Таким образом, определяющим в гипертонической устойчивости клеток является осмоляльность среды прединкубации, а не её ионная сила.----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- We studied here the effect of initial state of mammalian erythrocytes, formed under the effect of a partial dehydration on their sensitivity to hypertonic shock (4.0 mol/l NaCl). To determine the contribution of an increased ionic strength of the solution into the development of cell sensitivity to hypertonic shock, we used the moderate hypertonic sodium chloride (0.2-1.0 mol/l) and sucrose (0.2-1.2 mol/l) solutions as the preliminary dehydration media. For human, equine, rat and bovine erythrocytes the hemolytic dependences (4.0 mol/l NaCl) were revealed to have the minimum values under the certain values of sucrose and sodium chloride concentrations in the preincubation media. Moreover in case of bovine erythrocytes the maximum protection was observed under higher values of sodium chloride and sucrose concentrations. The minimum hypertonic damage in human, equine and rat erythrocytes was observed during preincubation in the solutions, containing sucrose in the following concentrations: 0.6 mol/l, 0.4 - 0.6 mol/l and 0.3 - 0.6 mol/l, respectively. When used the sodium chloride in the preincubation medium the minima of hemolytic dependencies of human, equine and rat erythrocytes were shifted to the left by X axis and made 0.35-0.4 mol/l, 0.3-0.4 mol/l, 0.2- 0.4 mol/l, respectively. The damage in bovine erythrocytes reached the minimum value after preincubating in the medium containing either sucrose or NaCl in 1.0 mol/l concentration. Rabbit erythrocytes had initially low damage in the medium with 4.0 mol/l NaCl and the preincubation in moderate hypertonic solutions caused no statistically significant effect on the level of their hypertonic hemolysis. The erythrocyte incubation in moderate hypertonic sodium chloride and sucrose solutions results in a partial dehydration, accompanied by an increased concentration of intracellular cations and the formation of more dense packed cytoskeletal proteins. We may assume both factors as contributing to an increased cell resistance to the effect of high hypertonic medium (4.0 mol/l NaCl). The maximum resistant state of rat, human and equine erythrocytes to hypertonic shock was demonstrated here as formed under conditions of cell preincubation in both saline and sucrose media, which osmolality made 400-800 mOsm/kg, 700-800 mosm/kg and 600-800 mOsm/kg, respectively. Thus, the preincubation medium osmolality, but not its ionic strength, is the determining factor in hypertonic resistance of cells. The formation of a steady state in bovine erythrocytes is observed in the media with higher sucrose and NaCl osmolality: 1300 and 1760 mOsm/kg, respectively. This may be due to the fact that in contrast to the other studied mammals, in bovine erythrocytes a predominant cation is the sodium, so the dehydration processes in bovine erythrocytes will have their own peculiarities.