CFTR mediates electrogenic chloride secretion in mouse inner medullary collecting duct (mIMCD-K2) cells.
CFTR mediates electrogenic chloride secretion in mouse inner medullary collecting duct (mIMCD-K2) cells.
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CFTR 介导小鼠内髓集合管 (mIMCD-K2) 细胞中的电化学氯化物分泌。
DOI：
10.1152/ajpcell.1995.269.3.c683
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
Stanton,BA
中科院分区：
文献类型：
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作者：
Vandorpe,D;Kizer,N;Ciampollilo,F;Moyer,B;Karlson,K;Guggino,WB;Stanton,BA
之前我们证明了内髓集合管细胞系 mIMCD-K2 通过生电机制分泌 Cl- [N. L. Kizer、B. Lewis 和 B. A. Stanton。是。 J.生理学。 268（肾液电解质生理学。37）：F347-F355，1995； N. L. Kizer、D. Vandope、B. Lewis、B. Bunting、J. Russell 和 B. A. Stanton。是。 J.生理学。 268（肾液电解质生理学。37）：F854-F861，1995]。本研究的目的是表征负责 3',5'-环单磷酸腺苷 (cAMP) 刺激 Cl- 分泌的 Cl- 通道。为此，我们使用膜片钳技术测量了 Cl- 电流。在全细胞膜片钳实验中，8-(4-氯苯硫基)腺苷3',5'-环单磷酸(CPT-cAMP)激活Cl-电流，该电流与时间和电压无关，被二苯胺2-羧酸酯(DPC)抑制，并且具有线性电流-电压(I-V)关系。在顶膜的细胞附着斑块中，我们鉴定了受 CPT-cAMP 刺激的 7-pS Cl- 通道。在移液管和浴液中含有 Cl- 的由内而外贴片中，Cl- 电流具有线性 I-V 关系。卤化物渗透率顺序为PCl = PBr > PI。 Cl-通道抑制剂DPC、5-硝基-2-(3-苯基丙氨基)-苯甲酸和格列本脲阻断7-pS Cl-通道，而4,4'-二异硫氰芪-2,2'-二磺酸无效。通过逆转录聚合酶链反应，我们在 mIMCD-K2 细胞中分离出了编码囊性纤维化跨膜电导调节因子的部分 cDNA 克隆。我们得出的结论是，cAMP 通过激活囊性纤维化跨膜电导调节器 Cl- 通道来刺激内髓集合管细胞中的电 Cl- 分泌。
Previously we demonstrated that the inner medullary collecting duct cell line mIMCD-K2 secretes Cl- by an electrogenic mechanism [N. L. Kizer, B. Lewis, and B. A. Stanton. Am. J. Physiol. 268 (Renal Fluid Electrolyte Physiol. 37): F347-F355, 1995; N. L. Kizer, D. Vandorpe, B. Lewis, B. Bunting, J. Russell, and B. A. Stanton. Am. J. Physiol. 268 (Renal Fluid Electrolyte Physiol. 37): F854-F861, 1995]. The goal of the present study was to characterize the Cl- channel responsible for adenosine 3',5'-cyclic monophosphate (cAMP)-stimulated Cl- secretion. To this end, using the patch-clamp technique, we measured Cl- currents. In whole cell patch-clamp experiments, 8-(4-chlorophenylthio)adenosine 3',5'-cyclic monophosphate (CPT-cAMP) activated Cl- currents that were time and voltage independent, inhibited by diphenylamine 2-carboxylate (DPC), and had a linear current-voltage (I-V) relation. In cell-attached patches of the apical membrane, we identified 7-pS Cl- channels that were stimulated by CPT-cAMP. In inside-out patches with Cl- in the pipette and bath solutions, Cl- currents had a linear I-V relation. The halide permeability sequence was PCl = PBr > PI. The Cl- channel inhibitors DPC, 5-nitro-2-(3-phenylpropylamino)-benzoic acid, and glibenclamide blocked the 7-pS Cl- channel, whereas 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid was ineffective. By reverse transcriptase polymerase chain reaction, we isolated a partial cDNA clone encoding the cystic fibrosis transmembrane conductance regulator in mIMCD-K2 cells. We conclude that cAMP stimulates electrogenic Cl- secretion in inner medullary collecting duct cells by activating cystic fibrosis transmembrane conductance regulator Cl- channels.