Muto S, Miyata Y, Asano Y
Department of Nephrology, Jichi Medical School, Tochigi, Japan.
J Clin Invest. 1993 Aug;92(2):571-81. doi: 10.1172/JCI116624.
Electrophysiological techniques were used to determine the electrical properties of the collecting duct (CD) cell in the isolated cortical collecting duct from obstructed (UUOOK) and contralateral (UUOCK) kidneys in rabbits 24 h after unilateral ureteral obstruction (UUO); results were compared with those from sham-operated kidneys. The lumen-negative transepithelial voltage and the basolateral membrane voltage (VB) were decreased in the UUOOK, and increased in the UUOCK. The transepithelial conductance (GT) was decreased in parallel with an increase in the fractional apical membrane resistance (fRA) and a decrease in apical membrane conductance in the UUOOK. By contrast, the GT was increased in parallel with increases in apical and basolateral membrane conductances in the UUOCK. The amiloride-sensitive changes in apical membrane voltage (VA), GT and fRA were lower in the UUOOK, but greater in the UUOCK. The changes in VA and GT upon raising the perfusate K+ concentration and upon addition of luminal Ba2+ were decreased in the UUOOK, and increased in the UUOCK. Addition of ouabain to the bath resulted in a smaller depolarization of VB in the UUOOK, but in a greater depolarization in the UUOCK. Upon lowering bath Cl-, the change in basolateral membrane electromotive force (delta EMF) was increased in the UUOOK, and decreased in the UUOCK. Reversely, upon raising bath K+, the delta EMF was decreased in the UUOOK, and increased in the UUOCK. We conclude: (a) the conductances of Na+ and K+ in the apical membrane, and active Na(+)-K+ pump activity and relative K+ conductance in the basolateral membrane are decreased in the UUOOK, and increased in the UUOCK; (b) the relative basolateral membrane Cl- conductance was increased in the UUOOK, and decreased in the UUOCK.
采用电生理技术测定家兔单侧输尿管梗阻（UUO）24小时后，梗阻侧（UUOOK）和对侧（UUOCK）肾脏分离皮质集合管（CD）细胞的电特性；将结果与假手术组肾脏进行比较。UUOOK中管腔负跨上皮电压和基底外侧膜电压（VB）降低，而UUOCK中升高。UUOOK中跨上皮电导（GT）降低，同时顶端膜电阻分数（fRA）增加，顶端膜电导降低。相反，UUOCK中GT升高，同时顶端和基底外侧膜电导增加。UUOOK中顶端膜电压（VA）、GT和fRA的氨氯地平敏感变化较低，但UUOCK中变化较大。升高灌注液K+浓度和加入管腔Ba2+后，UUOOK中VA和GT的变化降低，而UUOCK中升高。向浴槽中加入哇巴因后，UUOOK中VB的去极化较小，但UUOCK中去极化较大。降低浴槽Cl-浓度时，UUOOK中基底外侧膜电动势变化（δEMF）增加，而UUOCK中降低。相反，升高浴槽K+浓度时，UUOOK中δEMF降低，而UUOCK中升高。我们得出结论：（a）UUOOK中顶端膜中Na+和K+的电导、基底外侧膜中活性Na(+)-K+泵活性和相对K+电导降低，而UUOCK中升高；（b）UUOOK中基底外侧膜相对Cl-电导增加，而UUOCK中降低。
