Na-K-Cl cotransport in apical membrane of rabbit renal papillary surface epithelium.
Na-K-Cl cotransport in apical membrane of rabbit renal papillary surface epithelium.
复制标题
兔肾乳头表面上皮顶膜中的 Na-K-Cl 共转运。
DOI：
10.1152/ajprenal.1986.251.3.f475
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发表时间：
1986
期刊：
影响因子：
--
通讯作者：
K. Spring
中科院分区：
文献类型：
--
作者：
J. Sands;M. Knepper;K. Spring
肾乳头状表面上皮在其顶面暴露于盆腔尿液，在其基底外侧表面暴露于内髓间质。为了研究这种上皮细胞的运输，我们从兔的肾乳头中分离出它，并将其安装在一个允许两侧独立沐浴的小室中。使用计算机定量显微镜在25℃下测量细胞体积。将哇巴因(10(-4)M)加入到底侧溶液中，可引起20%的体积增加。去除根尖浴液中的氯化钠、钠、钾或氯离子可完全抑制这种体积的增加，但尿素的去除不能抑制这种体积的增加。在根尖浴液中加入10(-9)M的布美他尼可完全抑制哇巴因引起的肿胀。由于添加或去除氯化钠而引起的根尖细胞渗透压的变化，导致的细胞体积的变化比单独的渗透水流动更大。这种高反应可被布美他尼阻断，并被加压素(10(-8)M)刺激。这些观察结果与基底膜上的Na-K-ATPase和顶膜上布美他尼敏感、加压素反应的Na-K-Cl共转运体的存在是一致的。
The renal papillary surface epithelium is exposed to pelvic urine on its apical surface and to inner medullary interstitium on its basolateral surface. To investigate transport in this epithelium, we dissected it free from the renal papilla of rabbits and mounted it in a chamber that allowed both sides to be bathed independently. Cell volume was measured at 25 degrees C utilizing computerized quantitative microscopy. Addition of ouabain (10(-4) M) to the basolateral solution induced a 20% volume increase. This volume increase was completely inhibited by the removal of apical bath NaCl, Na+, K+, or Cl- but not by the removal of urea. Bumetanide, down to 10(-9) M in the apical bath, completely inhibited the ouabain-induced swelling. Changes in apical bath osmolality, resulting from addition or removal of NaCl, caused cell volume changes that were greater than could be accounted for by osmotic water flow alone. This hyperresponse was blocked by bumetanide and was stimulated by vasopressin (10(-8) M). These observations are consistent with the presence of Na-K-ATPase in the basolateral membrane and a bumetanide-sensitive, vasopressin-responsive Na-K-Cl co-transporter in the apical membrane.