Stanton B A
J Clin Invest. 1986 Dec;78(6):1612-20. doi: 10.1172/JCI112754.
Studies were conducted to examine the effects of adrenalectomy (ADX) and selective, physiological adrenal corticosteroid replacement on sodium and potassium transport by the superficial loop of Henle and distal tubule of rat kidney in vivo. In the loop of Henle, ADX inhibited sodium reabsorption by 33%. Whereas dexamethasone had no effect on reabsorption, aldosterone increased sodium transport to control levels. Thus, physiological levels of mineralocorticoids, but not glucocorticoids, control a fraction of sodium reabsorption in the loop of Henle. ADX also inhibited potassium reabsorption in the loop of Henle. Both dexamethasone and aldosterone reversed the inhibition, although only aldosterone increased reabsorption to control levels. In the distal tubule, ADX reduced sodium reabsorption by 44%. Both aldosterone and dexamethasone stimulated reabsorption: however, only aldosterone increased transport to control. Potassium secretion by the distal tubule was also reduced 34% by ADX. Aldosterone, but not dexamethasone, stimulated secretion. Thus, physiological levels of aldosterone regulate a fraction of sodium reabsorption and potassium secretion in the distal tubule.
开展了多项研究，以检测肾上腺切除术（ADX）以及选择性、生理性肾上腺皮质类固醇替代对大鼠肾脏髓袢升支粗段和远曲小管钠钾转运的影响。在髓袢升支粗段，ADX使钠重吸收减少33%。地塞米松对重吸收无影响，而醛固酮可使钠转运增加至对照水平。因此，盐皮质激素而非糖皮质激素的生理水平可调控髓袢升支粗段一部分钠的重吸收。ADX还抑制了髓袢升支粗段的钾重吸收。地塞米松和醛固酮均可逆转这种抑制作用，不过只有醛固酮能使重吸收增加至对照水平。在远曲小管，ADX使钠重吸收减少44%。醛固酮和地塞米松均刺激重吸收：然而，只有醛固酮能使转运增加至对照水平。ADX还使远曲小管的钾分泌减少34%。醛固酮而非地塞米松刺激分泌。因此，醛固酮的生理水平可调控远曲小管一部分钠的重吸收和钾的分泌。
