MICROPUNCTURE STUDY OF RENAL POTASSIUM EXCRETION IN RAT
MICROPUNCTURE STUDY OF RENAL POTASSIUM EXCRETION IN RAT
复制标题
DOI：
10.1152/ajplegacy.1964.206.4.674
复制
发表时间：
1964-01-01
影响因子：
--
通讯作者：
GIEBISCH, G
中科院分区：
文献类型：
--
作者：
MALNIC, G;KLOSE, RM;GIEBISCH, G
近端和远端肾小管液的样品收集保持在控制，低钾，或高钾，低钠饮食的大鼠。所有动物均接受菊粉-Cl 4。通过双通道微火焰光度法分析血浆（P）和肾小管液（TF）中的Na和K，并测定放射性。通过玻璃微电极测量前庭电位差。在所有动物组中，近端小管中钾的平均TF/P比值略低于1。比较K和菊粉-Cl 4沿着远端小管的相对增加表明：1）在大多数对照动物中，K净移动进入小管腔; 2）在高K、低Na、硫酸盐负荷的动物和对照饮食的双氯苯那胺处理的动物中，K净移动进入小管腔;和3）在保持低钾饮食的动物中，钾沿着远端小管，特别是集合管持续净重吸收的可能性。钾离子沿着电化学电位梯度进入远端肾小管。
Samples of proximal and distal tubular fluid were collected from rats maintained on a control, a low-K, or a high-K, low-Na diet. All animals received inulin-Cl4. Plasma (P) and tubular fluid (TF) were analyzed for Na and K by dual-channel microflame photometry and assayed for radioactivity. Transtubular electrical potential differences were measured by means of glass microelectrodes. Mean TF/P ratios for potassium in the proximal tubule were slightly below unity in all groups of animals. A comparison of the relative increase in K and inulin-Cl4 along the distal tubule indicates: 1) net movement of potassium into the tubular lumen in most control animals; 2) net movement of K into the tubular lumen of high-K, low-Na, sulfate -loaded animals, and in dichlorphenamide-treated animals on a control diet; and 3) the possibility of continued net reabsorption of potassium along the distal tubule and, particularly, the collecting duct in animals kept on a low-K diet. Distal tubular entry of potassium occurs down an electrochemical potential gradient.