Lacy E R
Cell Tissue Res. 1982;221(3):583-95. doi: 10.1007/BF00215702.
Antidiuretic hormone (ADH) induces an aggregation of intramembranous particles (IMP) into discrete clusters in the luminal plasma membrane of rat renal papillary collecting duct cells (Harmanci et al. 1978). The correlation between an elevated dose of ADH, increased urine osmolality, and greater IMP cluster frequency has led to speculation that the water permeability of the luminal plasma membrane is reflected by the IMP cluster density (Harmanci et al. 1980). The present study indirectly evaluated this water permeability by quantitating collecting duct IMP cluster frequency from freeze-fracture replicas in two regions of the renal papilla, at its base and at its tip, in antidiuretic and in water diuretic rats. During antidiuresis there was a high frequency of IMP clusters (189/100 micron2 of luminal plasma membrane) in cells from the papilla base but not at the papilla tip (9.0/100 micron2). During water diuresis there were few IMP clusters in either cells from the papilla base (5.9/100 micron2) or at the papilla tip (1.4/100 micron2). Most significantly these results suggest that the water permeability of the terminal portion of the inner medullary collecting duct of antidiuretic rats is significantly lower than that of the collecting duct epithelium higher in the papilla.
抗利尿激素（ADH）可诱导大鼠肾乳头集合管细胞管腔质膜中的膜内颗粒（IMP）聚集成离散的簇（哈曼奇等人，1978年）。ADH剂量升高、尿渗透压增加与IMP簇频率增加之间的相关性引发了一种推测，即管腔质膜的水通透性由IMP簇密度反映（哈曼奇等人，1980年）。本研究通过对禁水和水利尿大鼠肾乳头两个区域（基部和尖端）的冷冻蚀刻复制品中的集合管IMP簇频率进行定量，间接评估了这种水通透性。在禁水期间，乳头基部细胞中的IMP簇频率较高（管腔质膜每100平方微米有189个），而乳头尖端细胞中的IMP簇频率较低（每100平方微米有9.0个）。在水利尿期间，乳头基部细胞（每100平方微米有5.9个）和乳头尖端细胞（每100平方微米有1.4个）中的IMP簇都很少。最重要的是，这些结果表明，禁水大鼠内髓集合管末端部分的水通透性明显低于乳头中较高部位的集合管上皮细胞的水通透性。
