Chapman B E, Kuchel P W
Department of Biochemistry, University of Sydney, NSW, Australia.
Eur Biophys J. 1990;19(1):41-5. doi: 10.1007/BF00223572.
19F NMR spectra of sodium fluoride in suspensions of human erythrocytes were seen to yield separate resonances for the F- populations inside and outside the cells. Selective saturation of the magnetization of the intracellular population gave rise to transfer of that saturation to the extracellular population. The extent of magnetization transfer was high and it was blocked by the capnophorin (band 3) anion exchange inhibitor 4,4'-dinitrostilbene-2,2'-disulfonic acid (DNDS). A series of magnetization-inversion transfer experiments was carried out for the range of intracellular fluoride concentrations of 11 mM to 136 mM and analysed using one-dimensional 'overdetermined' exchange analysis. This yielded an estimate of the equilibrium exchange Michaelis constant and maximal velocity of 27 +/- 3 mM and 180 +/- 5 x 10(-16) mol cell-1 s-1, respectively. There was no alteration of exchange flux of fluoride at an intracellular concentration of 49 mM in the presence of 50 mM glucose; thus suggesting no interaction between glucose and anions in capnophorin-mediated exchange of solutes.
在人红细胞悬液中，氟化钠的19F核磁共振谱显示，细胞内外的F-群体产生了单独的共振峰。细胞内群体磁化的选择性饱和导致该饱和向细胞外群体转移。磁化转移程度很高，且被碳酸酐酶（带3）阴离子交换抑制剂4,4'-二硝基芪-2,2'-二磺酸（DNDS）阻断。针对细胞内氟浓度在11 mM至136 mM范围内进行了一系列磁化反转转移实验，并使用一维“超定”交换分析进行分析。这分别得出平衡交换米氏常数和最大速度的估计值为27±3 mM和180±5×10-16 mol细胞-1 s-1。在存在50 mM葡萄糖的情况下，细胞内浓度为49 mM时氟的交换通量没有改变；因此表明在碳酸酐酶介导的溶质交换中，葡萄糖和阴离子之间没有相互作用。
