Basolateral K channel activated by carbachol in the epithelial cell line T84
Basolateral K channel activated by carbachol in the epithelial cell line T84
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上皮细胞系 T84 中卡巴胆碱激活的基底外侧 K 通道
DOI：
10.1007/bf00234946
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
J. Hanrahan
中科院分区：
文献类型：
--
作者：
J. Tabcharani;R. Harris;A. Boucher;J. W. Eng;J. Hanrahan
胆碱能刺激氯化物分泌涉及激活的基底外侧膜钾电导，保持有利于顶端Cl流出的电梯度，并允许K在基底外侧膜再循环。我们已经使用跨上皮短路电流（ISC），荧光成像和膜片钳研究，以确定和表征的K通道，介导T84细胞的这种反应。卡巴胆碱对ISC的影响不大，单独加入时，但产生大，瞬态电流，如果加入到单细胞膜prestimulated与cAMP。cAMP还增强了随后的ISC对钙离子载体的反应。卡巴胆碱（100 μm）可使在盖玻片上培养的融合细胞的细胞内游离钙（[Ca 2 +]i）瞬时升高约3倍，其时间过程类似于在多孔支持物上生长的融合单层的Isc反应。在平行膜片钳实验中，卡巴胆碱激活了一个内向整流钾通道的基底侧方面的极化单层已被解剖的多孔文化支持。在卡巴胆碱刺激过程中，在亚汇合单层的表面上瞬时激活相同的通道。当细胞暴露于钙离子载体时，激活时间更长。在含有150 mm KCl（37°C）的移液器溶液中，细胞贴附贴片中内向整流器的电导在静息膜电位（−54 mV）附近为55 pS。当贴片浸泡在对称的150 mm KCl溶液中时，这种矫正持续存在。在双离子条件下，根据渗透率比，选择性顺序为1 K > 0.88 Rb > 0.18 Na> Cs。该通道可被钠离子快速阻断，被TEA弱抑制，对卡里巴毒素、钾毒素、4-氨基吡啶和奎尼丁不敏感，不受10 mm钡的影响。它被称为KBIC通道，基于其最独特的特性（Ba不敏感，向内整流，Ca激活）。像单个KBIC通道一样，卡巴胆碱刺激的ISC对基底侧的几种阻断剂相对不敏感，并且不受钡的影响。宏观电流和单通道的性质之间的这些比较表明，KBIC通道介导的基底外侧膜K电导在T84细胞单层的胆碱能促分泌素刺激期间。
Cholinergic stimulation of chloride secretion involves the activation of a basolateral membrane potassium conductance, which maintains the electrical gradient favoring apical Cl efflux and allows K to recycle at the basolateral membrane. We have used transepithelial short-circuit current (ISC), fluorescence imaging, and patch clamp studies to identify and characterize the K channel that mediates this response in T84 cells. Carbachol had little effect on ISC when added alone but produced large, transient currents if added to monolayers prestimulated with cAMP. cAMP also enhanced the subsequent ISC response to calcium ionophores. Carbachol (100 μm) transiently elevated intracellular free calcium ([Ca2+]i) by ∼3-fold in confluent cells cultured on glass coverslips with a time course resembling the Isc response of confluent monolayers that had been grown on porous supports. In parallel patch clamp experiments, carbachol activated an inwardly rectifying potassium channel on the basolateral aspect of polarized monolayers which had been dissected from porous culture supports. The same channel was transiently activated on the surface of subconfluent monolayers during stimulation by carbachol. Activation was more prolonged when cells were exposed to calcium ionophores. The conductance of the inward rectifier in cell-attached patches was 55 pS near the resting membrane potential (−54 mV) with pipette solution containing 150 mm KCl (37°C). This rectification persisted when patches were bathed in symmetrical 150 mm KCl solutions. The selectivity sequence was 1 K > 0.88 Rb > 0.18 Na ≫ Cs based on permeability ratios under bi-ionic conditions. The channel exhibited fast block by external sodium ions, was weakly inhibited by external TEA, was relatively insensitive to charybdotoxin, kaliotoxin, 4-aminopyridine and quinidine, and was unaffected by external 10 mm barium. It is referred to as the KBIC channel based on its most distinctive properties (Ba-insensitive, inwardly rectifying, Ca-activated). Like single KBIC channels, the carbachol-stimulated ISC was relatively insensitive to several blockers on the basolateral side and was unaffected by barium. These comparisons between the properties of the macroscopic current and single channels suggest that the KBIC channel mediates basolateral membrane K conductance in T84 cell monolayers during stimulation by cholinergic secretagogues.
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气管上皮中的钾电导由分泌和细胞肿胀激活。
DOI：
10.1152/ajpcell.1990.258.4.c630
发表时间：
1990
期刊：
The American journal of physiology
影响因子：
--
作者：
Butt,AG;Clapp,WL;Frizzell,RA
通讯作者：
Frizzell,RA
气道上皮的基底外侧 K 通道。
DOI：
10.1152/ajplung.1990.258.6.l334
发表时间：
1990
期刊：
The American journal of physiology
影响因子：
--
作者：
McCann,JD;Matsuda,J;Garcia,M;Kaczorowski,G;Welsh,MJ
通讯作者：
Welsh,MJ
影响因子：
4
作者：
R. Tsien;A. Harootunian
通讯作者：
R. Tsien;A. Harootunian
四磷酸肌醇的升高与T84细胞中Ca(2)依赖性Cl-分泌的抑制平行。
DOI：
10.1152/ajpcell.1993.264.3.c671
发表时间：
1993
期刊：
The American journal of physiology
影响因子：
--
作者：
Kachintorn,U;Vajanaphanich,M;Barrett,KE;Traynor-Kaplan,AE
通讯作者：
Traynor-Kaplan,AE
蛋白激酶 C 介导 Cl(-) 分泌上皮细胞中胆碱能调节的蛋白质磷酸化。
DOI：
10.1152/ajpcell.1990.258.2.c227
发表时间：
1990
期刊：
The American journal of physiology
影响因子：
--
作者：
Cohn,JA
通讯作者：
Cohn,JA