Characterization of two distinct chloride channels in cultured dog pancreatic duct epithelial cells.
Characterization of two distinct chloride channels in cultured dog pancreatic duct epithelial cells.
复制标题
培养的狗胰管上皮细胞中两种不同氯离子通道的表征。
DOI：
10.1152/ajpgi.1997.272.1.g172
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发表时间：
1997
期刊：
影响因子：
--
通讯作者：
Lee,SP
中科院分区：
文献类型：
--
作者：
Nguyen,TD;Koh,DS;Moody,MW;Fox,NR;Savard,CE;Kuver,R;Hille,B;Lee,SP
胰管上皮细胞 (PDEC) 分泌的 Cl- 调节细胞 HCO3- 分泌，这是胰腺外分泌的重要组成部分。例如，在囊性纤维化中，囊性纤维化跨膜电导调节因子（CFTR）Cl-通道的功能受损会导致胰腺分泌减少和继发性胰腺功能不全。由于缺乏实用的体外模型，PDEC 离子转运的研究受到阻碍。我们已成功在覆盖肌成纤维细胞饲养层的 Vitrogen 涂层渗透膜上培养未转化的狗 PDEC，并报告了这些细胞中 Cl-通道的特征。 Cl-电导通过 125I 从 PDEC 流出进行评估，并受到通过腺苷 3',5'-环单磷酸 (cAMP) 或胞质 Ca2+ 作用的药物的刺激。 cAMP 和 Ca2+ 激活的 Cl- 电导是不同的，因为它们受到 4,4'-二异硫氰芪-2,2'-二磺酸的不同抑制，并且在较小程度上受到 5-硝基-2-(3-苯基丙氨基)苯甲酸和二苯胺-2 羧酸盐的抑制。膜片钳研究证实存在由 cAMP 和 Ca2+ 激活的 Cl- 通道，并受到 4,4'-二异硫氰芪-2,2'-二磺酸的不同抑制。通过免疫印迹证实PDEC中CFTR Cl-通道的存在。这些培养的 PDEC 是研究胰管分泌的最佳模型。
Cl- secretion by pancreatic duct epithelial cells (PDEC) regulates cellular HCO3- secretion, an important component of the exocrine pancreas. In cystic fibrosis, for example, impaired function of the cystic fibrosis transmembrane conductance regulator (CFTR) Cl- channel results in decreased pancreatic secretion and secondary pancreatic insufficiency. Studies of ion transport by PDEC have been hindered by the lack of a practical in vitro model. We have successfully cultured nontransformed dog PDEC on Vitrogen-coated permeable membranes overlying a feeder layer of myofibroblasts and report the characterization of Cl- channels in these cells. Cl- conductance, assessed through efflux of 125I from PDEC, was stimulated by agents acting via adenosine 3',5'-cyclic monophosphate (cAMP) or cytosolic Ca2+. The Cl- conductances activated by cAMP and Ca2+ were distinct, since they were differentially inhibited by 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid and, to a lesser extent, by 5-nitro-2-(3-phenylpropylamino)benzoic acid and diphenylamine-2 carboxylate. Patch-clamp studies confirmed the presence of Cl- channels activated by cAMP and Ca2+, with differential inhibition by 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid. The presence of CFTR Cl- channels in PDEC was confirmed by immunoblotting. These cultured PDEC are an optimal model for studies of pancreatic duct secretion.