Selective erythrocyte potassium efflux following pulse treatment with tellurite.
Selective erythrocyte potassium efflux following pulse treatment with tellurite.
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DOI：
10.1002/jbt.2570060403
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发表时间：
1991-12
期刊：
影响因子：
--
通讯作者：
R. Klug;J. Kurantsin-Mills
中科院分区：
文献类型：
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作者：
R. Klug;J. Kurantsin-Mills
人红细胞暴露于等渗缓冲氯化胆碱介质中的0.1 mM亚碲酸盐（K2 TeO 3），在37 ℃下持续15分钟，洗涤，并在缓冲液中不存在化学物质的情况下进一步孵育，在几分钟内表现出钾的选择性泄漏。钾外流曲线呈S形，最初缓慢泄漏，随后急剧上升（一级动力学）和60分钟的平台。15分钟后，30-50%的总钾浓度已泄漏的细胞，虽然不到1%的溶解发生。在不含K2 TeO 3的缓冲液中孵育的对照细胞未表现出钾渗漏。K2 TeO 3处理的红细胞的平均体积增加，其密度中位数下降，表明胶体渗透状态和物理特性的细胞的变化。然而，与用叔丁基氢过氧化物预处理的细胞不同，用K2 TeO 3预处理的细胞在谷胱甘肽（GSH）浓度方面没有显著变化，并且没有膜脂质过氧化（Deuticke et al.，生物化学生物Acta，899，125-128，1987）。K2 TeO 3处理的红细胞的钾渗透性增强之前的细胞体积，细胞内水化的增加，和减少中位密度。我们认为，氧化剂在膜中的脂质-蛋白质相互作用的扰动改变了钾的渗透性，并导致最终溶血的选择性泄漏。
Human erythrocytes exposed to 0.1 mM tellurite (K2TeO3) in an isotonic buffered choline chloride medium for 15 min at 37 degrees C, washed, and incubated further in the absence of the chemical in the buffer, exhibited selective leakiness for potassium within minutes. The potassium efflux curve was sigmoidal, with an initially slow leakage followed by a sharp rise (first-order kinetics) and a plateau by 60 min. After 15 min, 30-50% of the total potassium concentration had leaked from the cells, although less than 1% lysis had occurred. The control cells incubated in buffer with no K2TeO3 exhibited no potassium leakage. The mean volume of the K2TeO3-treated erythrocytes increased and their median density decreased, indicating changes in the colloid osmotic state and physical characteristics of the cells. However, cells pretreated with K2TeO3 exhibited no significant change in glutathione (GSH) concentration and no membrane lipid peroxidation, unlike cells pretreated with t-butylhydroperoxide (Deuticke et al., Biochim. Bio phys. Acta, 899, 125-128, 1987). The enhanced potassium permeability of the K2TeO3-treated erythrocytes preceded the increase in cell volume, intracellular hydration, and a decrease in median density. We suggest that perturbation of the lipid-protein interaction in the membrane by the oxidant alters the potassium permeability and results in the selective leakage with eventual hemolysis.