Villamil M F, Kleeman C R
J Gen Physiol. 1969 Nov;54(5):576-88. doi: 10.1085/jgp.54.5.576.
Na efflux of rabbit RBC is approximately 10 mmoles/kg wet weight. hr. One-half of this consists of a ouabain-insensitive exchange diffusion component. Ouabain inhibits 2.5 mmoles/kg.hr of Na efflux. K influx is 3.0 mmoles/kg.hr; 2.2 mmoles/kg.hr are inhibited by ouabain. In contrast with human RBC, ouabain inhibition of Na efflux and K influx of rabbit RBC is easily reversible. After 2 hr, ouabain inhibition of Na efflux is completely compensated for by increased internal Na concentration and Na efflux returns to initial levels. Removal of ouabain at this stage results in stimulation of the efflux by 4.3 mmoles/kg.hr. Na influx is initially not affected by ouabain but is increased by 2.4 mmoles/kg.hr after 2 hr incubation with the drug. Removal of K from normal Ringer does not affect Na efflux and increases Na influx by 1.6 mmoles/kg.hr. Addition of ouabain to K-free Ringer inhibits Na efflux and influx to the same extent (1.6 mmoles/kg.hr). Removal of Na from K-free Ringer has an inhibitory effect on efflux similar to that of ouabain. These findings suggest that the fraction of Na efflux inhibited by removal of external K is completely replaced by a new, ouabain-sensitive exchange diffusion of Na ions.
兔红细胞的钠外流约为10毫摩尔/千克湿重·小时。其中一半由哇巴因不敏感的交换扩散成分组成。哇巴因抑制2.5毫摩尔/千克·小时的钠外流。钾内流为3.0毫摩尔/千克·小时；2.2毫摩尔/千克·小时被哇巴因抑制。与人类红细胞不同，哇巴因对兔红细胞钠外流和钾内流的抑制很容易逆转。2小时后，哇巴因对钠外流的抑制作用完全被细胞内钠浓度升高所补偿，钠外流恢复到初始水平。在此阶段去除哇巴因会导致外流刺激增加4.3毫摩尔/千克·小时。钠内流最初不受哇巴因影响，但与该药物孵育2小时后增加2.4毫摩尔/千克·小时。从正常林格液中去除钾不影响钠外流，使钠内流增加1.6毫摩尔/千克·小时。向无钾林格液中添加哇巴因对钠外流和内流的抑制程度相同（1.6毫摩尔/千克·小时）。从无钾林格液中去除钠对外流有类似于哇巴因的抑制作用。这些发现表明，去除细胞外钾所抑制的那部分钠外流完全被一种新的、对哇巴因敏感的钠离子交换扩散所取代。
