Cell sodium-induced recruitment of Na(+)-K(+)-ATPase pumps in rabbit cortical collecting tubules is aldosterone-dependent.
Cell sodium-induced recruitment of Na(+)-K(+)-ATPase pumps in rabbit cortical collecting tubules is aldosterone-dependent.
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兔皮质集合管中细胞钠诱导的 Na( )-K( )-ATPase 泵的募集是醛固酮依赖性的。
DOI：
10.1016/s0021-9258(19)38450-9
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发表时间：
1990
期刊：
影响因子：
--
通讯作者：
N. Farman
中科院分区：
文献类型：
--
作者：
M. Blot;F. Wanstok;J. Bonvalet;N. Farman
研究了不同醛固酮条件下兔肾皮质集合管(CCD)中细胞内钠浓度([Na+]i)对Na(+)-K(+)-ATP酶泵数量的影响。在具有各种[Na+]i的隔离CCD中测量特异性[3H]哇巴因结合。对仅接受替代剂量的地塞米松的肾上腺切除的兔子和充满醛固酮的肾上腺切除的兔子进行了实验。在醛固酮充足的兔子中，结合位点的数量随[Na+]i线性增加，从15 mM Na+i下的16 fmol/nl肾小管体积增加到140 mM Na+i下的39 fmol/nl肾小管体积。放线菌素 D (5 µM) 和放线菌酮 (10 µM) 均不能阻止这种 [Na+]i 依赖性增加。在肾上腺切除的兔子中，哇巴因结合位点的数量随着[Na+]i的增加而减少，并且没有增加。这些结果支持 CCD 中存在“潜在”泵池，并在 [Na+]i 影响下快速招募。醛固酮似乎是该池的构成和/或激活所必需的。
The influence of intracellular sodium concentration ( [Na+]i) on the number of Na(+)-K(+)-ATPase pumps was examined in cortical collecting tubules (CCD) of kidneys from rabbits in different aldosterone conditions. Specific [3H]ouabain binding was measured in isolated CCD with various [Na+]i. Experiments were performed on adrenalectomized rabbits receiving only a substitutive dose of dexamethasone and on adrenalectomized rabbits replete with aldosterone. In aldosterone-replete rabbits, the number of binding sites increased linearly with [Na+]i, from 16 fmol/nl tubular volume at 15 mM Na+i to 39 fmol/nl tubular volume at 140 mM Na+i. Neither actinomycin D (5 microM) nor cycloheximide (10 microM) prevented this [Na+]i-dependent increase. In adrenalectomized rabbits, the number of ouabain-binding sites was reduced and did not increase with [Na+]i. These results are in favor of the presence of a "latent" pool of pumps in CCD, rapidly recruited under [Na+]i influence. Aldosterone appears to be required for the constitution and/or activation of this pool.