Intracellular potentials in rabbit proximal tubules perfused in vitro.
Intracellular potentials in rabbit proximal tubules perfused in vitro.
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体外灌注兔近曲小管的细胞内电位。
DOI：
10.1152/ajprenal.1981.240.3.f200
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发表时间：
1981
期刊：
影响因子：
--
通讯作者：
Giebisch,G
中科院分区：
文献类型：
--
作者：
Biagi,B;Kubota,T;Sohtell,M;Giebisch,G
使用常规微电极测量兔肾的分离灌注浅表近曲小管（sPCT）和浅表近端直管（sPST）中的基底外侧膜电位（VBL）。可以获得长达 2 小时的稳定记录。 VBL 的平均 +/- SE（n = 细胞数）值为 sPCT = -51.0 +/- 1.63 (24) 和 sPST = -47.0 +/- 0.97 (94) mV。主动转运抑制剂哇巴因 (10(-5) M) 和低浴钾 (0.1 mM) 引起 sPST 中 VBL 的显着去极化。相比之下，短时间水浴冷却（10 摄氏度）则没有显着影响。去除腔内葡萄糖导致 sPCT 中的超极化 (-13.9 +/- 1.77 (9) mV) 比 sPST (-3.8 +/- 1.02 (5) mV) 更大。去除管腔葡萄糖和丙氨酸导致 sPCT 中 VBL 的超极化更大（-19.0 +/- 0.44 (6) mV）。用类似于 sPST 中晚期近端肾小管液体的溶液灌注管腔导致 VBL 超极化 (-4.3 +/- 0.85 (4) mV)。将浴液 pH 值降低至 6.7 去极化 VBL (39.9 +/- 1.77 (13) mV)。这种效应可能与基底外侧膜相对钾渗透性的降低有关。这些结果证明了使用细胞内电测量来确定孤立的近端管状节段的管腔和基底外侧膜特征的可行性。
Conventional microelectrodes were used to measure the basolateral membrane potential (VBL) in isolated perfused superficial proximal convoluted (sPCT) and superficial proximal straight (sPST) tubules of the rabbit kidney. Stable recordings for periods up to 2 h can be obtained. The mean +/- SE (n = number of cells) values of VBL were sPCT = -51.0 +/- 1.63 (24) and sPST = -47.0 +/- 0.97 (94) mV. Inhibitors of active transport, ouabain (10(-5) M) and low bath potassium (0.1 mM), caused a significant depolarization of VBL in sPST. In contrast, short-duration bath cooling (10 degrees C) had no significant effect. Removal of luminal glucose caused a larger hyperpolarization in sPCT (-13.9 +/- 1.77 (9) mV) than in sPST (-3.8 +/- 1.02 (5) mV). Removal of luminal glucose and alanine resulted in an even larger hyperpolarization of VBL in sPCT (-19.0 +/- 0.44 (6) mV). Perfusion of the lumen with a solution resembling late proximal tubular fluid in sPST resulted in hyperpolarization of VBL (-4.3 +/- 0.85 (4) mV). Reducing bath pH to 6.7 depolarized VBL (39.9 +/- 1.77 (13) mV). This effect can be associated with a decrease in the relative potassium permeability of the basolateral membrane. These results demonstrate the feasibility of using intracellular electrical measurements to determine both luminal and basolateral membrane characteristics in isolated proximal tubular segments.