Garg L C, Knepper M A, Burg M B
Am J Physiol. 1981 Jun;240(6):F536-44. doi: 10.1152/ajprenal.1981.240.6.F536.
A fluorometric micromethod for the assay of Na-K-ATPase was used to determine Na-K-ATPase activity in 11 segments of the rabbit nephron. The Na-K-ATPase activity was found to be highest (greater than 100 pmol.mm1-.min-1) in proximal convoluted tubules (S1), medullary thick ascending limbs, distal convoluted tubules, and connecting tubules. There was a good correlation (r = 0.94) between Na-K-ATPase activity in different segments and net Na transport previously measured by in vitro tubule perfusion. Treatment of rabbits with deoxycorticosterone (DOCA) for 8-11 days produced increases in Na-K-ATPase activity of 100 and 500% in connecting tubules and cortical collecting ducts, respectively, without significant change in other segments. Maintenance on a low sodium diet for 12-18 days was associated with a 200% increase in Na-K-ATPase activity in cortical collecting ducts only. We conclude that the Na-K-ATPase activity is stimulated by mineralocorticoids in the cortical collecting duct in association with the previously observed changes in sodium transport.
采用一种荧光微量法测定兔肾单位11个节段中的钠钾ATP酶活性。结果发现，近端曲管（S1）、髓质厚升支、远端曲管和连接管中的钠钾ATP酶活性最高（大于100 pmol·mm⁻¹·min⁻¹）。不同节段的钠钾ATP酶活性与先前通过体外肾小管灌注测量的净钠转运之间存在良好的相关性（r = 0.94）。用脱氧皮质酮（DOCA）处理兔子8 - 11天，连接管和皮质集合管中的钠钾ATP酶活性分别增加了100%和500%，而其他节段无明显变化。仅在低钠饮食维持12 - 18天时，皮质集合管中的钠钾ATP酶活性增加了200%。我们得出结论，盐皮质激素刺激皮质集合管中的钠钾ATP酶活性，这与先前观察到的钠转运变化有关。
