Electrical properties of the medullary collecting duct in the rat.
Electrical properties of the medullary collecting duct in the rat.
复制标题
大鼠髓质集合管的电特性。
DOI：
10.1152/ajprenal.1980.239.3.f258
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发表时间：
1980
期刊：
影响因子：
--
通讯作者：
Schon,DA
中科院分区：
文献类型：
--
作者：
Hayslett,JP;Backman,KA;Schon,DA
在大鼠实验中测定了髓质集管（MCD）的经上皮电位差（PD）。微导管作为探查电极，从导管管腔到放置在腹膜液中的参比电极的PD在MCD中约为1mv，管腔阳性。极性和小幅度的PD不太可能是由微导管产生的伪像造成的，因为使用Ling-Gerard玻璃电极和玻璃微电极（尖端外径3-5微米）对导管内三分之一进行透壁穿刺获得的结果基本上相似。此外，在实验状态下，观察到几毫伏的PD，管腔阳性，其特征是钾和氢离子分泌和钠吸收显著增加。进一步研究表明，由于乳头区NaCl浓度较高，乳头与参比电极之间的间质液腔内的扩散电位约为+2 mV。因此，这些数据表明，在对照动物中，MCD的经上皮PD接近于零，并且没有因净电解质运输的显着变化而发生实质性改变。
Studies were performed in the rat to determine the transepithelial potential difference (PD) of the medullary collecting duct (MCD). With the microcatheter as an exploring electrode the PD from duct lumen to the reference electrode, placed in peritoneal fluid, was approximatley 1 mV, lumen positive, in the MCD. It was unlikely that the polarity and small magnitude of PD was due to an artifact created by the microcatheter, since essentially similar results were obtained by transmural puncture of the inner third of the duct using Ling-Gerard glass electrodes and glass microelectrodes, tip OD 3-5 micron. Moreover, a PD of a few millivolts, lumen positive, was observed in experimental states characterized by marked increases in potassium and hydrogen ion secretion and sodium absorption. Further studies showed that the diffusion potential existing within the interstitial fluid compartment, between papilla and reference electrode, was approximately +2 mV, owing to the higher NaCl concentration in the papillary area. These data demonstrate, therefore, that the transepithelial PD in MCD approaches zero in control animals, and is not substantially altered by marked changes in net electrolyte transport.