Changes in the water and ion contents of rabbit renal cortical slices, which had been bathed, immediately after slicing, in air-equilibrated media at room temperature ('freshly prepared slices'), were followed during subsequent incubation at 25 degrees C in oxygenated media of the same composition as the initial bathing medium. 2. In comparison with conventional 'equilibrated' slices (slices incubated at 25 degrees C in oxygenated ordinary medium immediately after slicing) these 'freshly prepared' slices had increased tissue water, sodium and chloride contents and low tissue potassium contents. 3. Control freshly prepared slices incubated at 25 degrees C in oxygenated ordinary medium recovered within 4 min to the tissue water content that is usual for rabbit renal cortical slices incubated in oxygenated ordinary medium at 25 degrees C. Freshly prepared slices incubated at 25 degrees C in oxygenated media containing 1 mM-oubain took 75 min or more to recover to this usual tissue water content. Thus the presence of 1 mM-oubain in both bathing and incubation media produced a marked inhibition of the volume recovery observed when freshly prepared slices are incubated in oxygenated media at 25 degrees C. 4. Reduction of the ouabain concentration reduced the inhibition of cell volume recovery. 5. Replacement of medium glucose by 3-O-methylglucose did not inhibit cell volume recovery in the absence of ouabain. 6. The oxygen consumptions of slices that were bathed and incubated in 1 mM-ouabain media were similar to those of slices initially bathed and incubated in ouabain-free media and then incubated in ouabain media. Thus the effect of ouabain in inhibiting cell volume recovery was unlikely to be secondary to inhibition of cellular energy production. 7. The tissue potassium content of slices incubated aerobically in 1 or 10 mM ouabin fell to an apparently stable value of approximately 100 m-mole/kg dry wt., which corresponds to a calculated concentration ratio of 10:1 across the cellular membrane, suggesting that some residual potassium uptake may still have been occurring. 8. These results indicate that in freshly prepared rabbit renal cortical slices ouabain-sensitive mechanisms play a major role in cell volume recovery. They are not in accord with the postulate that renal cortical cells possess a separate ouabain-insensitive mechanism regulating cell volume.
摘要
将兔肾皮质切片在室温下切成薄片后立即置于与空气平衡的介质中（“新鲜制备的切片”），随后在25℃下于与初始浸泡介质成分相同的充氧介质中孵育，观察其水和离子含量的变化。2. 与传统的“平衡”切片（切片切成后立即在25℃下于充氧普通介质中孵育）相比，这些“新鲜制备的”切片组织含水量、钠和氯含量增加，组织钾含量降低。3. 在25℃下于充氧普通介质中孵育的对照新鲜制备切片在4分钟内恢复到在25℃下于充氧普通介质中孵育的兔肾皮质切片通常的组织含水量。在25℃下于含1 mM哇巴因的充氧介质中孵育的新鲜制备切片需要75分钟或更长时间才能恢复到这个通常的组织含水量。因此，在浸泡和孵育介质中存在1 mM哇巴因会显著抑制新鲜制备切片在25℃下于充氧介质中孵育时观察到的体积恢复。4. 降低哇巴因浓度可减少对细胞体积恢复的抑制。5. 在没有哇巴因的情况下，用3 - O - 甲基葡萄糖替代介质葡萄糖不会抑制细胞体积恢复。6. 在1 mM哇巴因介质中浸泡和孵育的切片的氧消耗量与最初在无哇巴因介质中浸泡和孵育然后在哇巴因介质中孵育的切片相似。因此，哇巴因抑制细胞体积恢复的作用不太可能继发于对细胞能量产生的抑制。7. 在1或10 mM哇巴因中需氧孵育的切片的组织钾含量降至约100 m - 摩尔/千克干重的明显稳定值，这对应于跨细胞膜计算的浓度比为10:1，表明可能仍有一些残余的钾摄取在发生。8. 这些结果表明，在新鲜制备的兔肾皮质切片中，哇巴因敏感机制在细胞体积恢复中起主要作用。它们与肾皮质细胞具有独立的对哇巴因不敏感的调节细胞体积机制的假设不一致。
