Dwight J F, Hendry B M
Department of Medicine, King's College School of Medicine and Dentistry, London, UK.
Clin Chim Acta. 1995 Jul 14;238(2):187-97. doi: 10.1016/0009-8981(95)06090-z.
The effects of non-esterified arachidonic acid (AA) on erythrocyte membrane ion permeability have been studied using 86Rb flux measurements. [14C]AA was used to quantify membrane incorporation of AA and to show AA removal by albumin washing. The actions of vitamin E and other antioxidants on the effects of AA were examined. Reversible membrane incorporation of 700-2000 nmol AA per ml cells was achieved without significant haemolysis or morphological change. AA incorporation caused a reversible mean increase in bumetanide-sensitive Rb influx of 34% (S.E.M. 4.5, n = 23). This action could be partially prevented by co-incubation with vitamin E, but not by Trolox or dithioerythritol. AA incorporation caused an irreversible mean increase in residual Rb permeability (bumetanide and ouabain insensitive) of 130% (S.E.M. 22, n = 20), associated with a rise in intracellular Na and a fall in intracellular K concentrations. This action was also partially prevented by co-incubation with vitamin E. The effects of AA incorporation on Na,K-ATPase function were difficult to quantify because of the concomitant rises in intracellular Na but the data are consistent with approximately 20% inhibition of activity. Modulation of membrane ion permeability by AA appears to be partially mediated by lipid peroxidation and may have pathophysiological significance.
利用⁸⁶Rb通量测量研究了非酯化花生四烯酸（AA）对红细胞膜离子通透性的影响。使用[¹⁴C]AA来量化AA在膜中的掺入情况，并通过白蛋白洗涤来显示AA的去除情况。研究了维生素E和其他抗氧化剂对AA作用的影响。每毫升细胞可逆性掺入700 - 2000 nmol AA，且无明显溶血或形态变化。AA掺入导致布美他尼敏感的Rb内流平均可逆性增加34%（标准误4.5，n = 23）。与维生素E共同孵育可部分阻止此作用，但与生育三烯酚或二硫苏糖醇共同孵育则不能。AA掺入导致残余Rb通透性（对布美他尼和哇巴因不敏感）平均不可逆性增加130%（标准误22，n = 20），同时细胞内Na升高，细胞内K浓度降低。与维生素E共同孵育也可部分阻止此作用。由于细胞内Na同时升高，难以量化AA掺入对Na，K - ATP酶功能的影响，但数据表明活性受到约20%的抑制。AA对膜离子通透性的调节似乎部分由脂质过氧化介导，可能具有病理生理学意义。
