Gus'kova R A, Ivanov I I, Kol'tover V K, Akhobadze V V, Rubin A B
Biokhimiia. 1984 May;49(5):758-66.
Lecithin monolayer liposomes (1000 A in diameter) loaded with cytochrome c were placed into the external solution, in which O2 superoxide radicals were regenerated by the xanthine-xanthine oxidase system. The penetration of superoxide radicals across the liposomal membranes was followed by cytochrome c reduction in the interval volume of the liposomes. The effects of lipid membrane modifiers and temperature on this process were investigated. The results obtained were used for calculation of the permeability coefficients of bilayer lipid membranes for O(2) (P'O(2) = (7.6 +/- 0.3) . 10(-8) cm . s-1) or HO . 2(P'HO(2) = 4.9 x 10(-4) cm . s-1). The effect of the transmembrane electric potential (concentration gradient of H+, valinomycin) on the permeability of liposomal membranes for the superoxide radical was studied. The superoxide radical was down to penetrate across the bilayer lipid membranes in an unloaded state. Using an intramolecular cholesterol-amphotericin B-complex, the superoxide radicals were shown to penetrate across the bilayer lipid membranes, predominantly via the anionic channels.
将负载细胞色素c的卵磷脂单层脂质体（直径1000埃）置于外部溶液中，在该溶液中，超氧阴离子自由基通过黄嘌呤 - 黄嘌呤氧化酶系统再生。通过脂质体间隔体积中的细胞色素c还原跟踪超氧阴离子自由基穿过脂质体膜的渗透情况。研究了脂质膜修饰剂和温度对该过程的影响。所得结果用于计算双层脂质膜对O₂（P'O₂ = (7.6 ± 0.3)·10⁻⁸ cm·s⁻¹）或HO₂（P'HO₂ = 4.9 x 10⁻⁴ cm·s⁻¹）的渗透系数。研究了跨膜电势（H⁺浓度梯度，缬氨霉素）对脂质体膜对超氧阴离子自由基渗透性的影响。超氧阴离子自由基在未负载状态下难以穿过双层脂质膜。使用分子内胆固醇 - 两性霉素B复合物，表明超氧阴离子自由基主要通过阴离子通道穿过双层脂质膜。
