Calcium ionophore plus excision induce a large conductance chloride channel in membrane patches of human colon carcinoma cells HT-29cl.19A |
| |
| Authors: | R B Bajnath J A Groot H R de Jonge M Kansen J Bijman |
| |
| Institution: | (1) Department of Experimental Zoology, University of Amsterdam, Kruislaan 320, 1098 SM Amsterdam, (The Netherlands);(2) Department of Biochemistry 1, Erasmus University, Rotterdam, (The Netherlands);(3) Department of Cell Biology, Erasmus University, Rotterdam, (The Netherlands) |
| |
| Abstract: | In excised inside-out membrane patches of the human colon carcinoma HT-29cl.19A cells a large conductance (373±10 pS) chloride channel was found. Channel activity could only be observed after excision of patches from cells incubated with calcium ionophore. The channel was never observed in cell-attached patches. The channel was strongly voltage dependent, being open only between +30 and –30 mV clamp potentials. The selectivity sequence among anions, deduced from reversal potentials, was I>Br>Cl>F>gluconate. The PNa/PCl was 0.09. Although a similar type of channel, has been described earlier, this is the first report stating its appearance in patches of intestinal epithelial cells requiring the combined action of Ca2+ ionophore and excision, suggesting its control by an intracellular compound. |
| |
| Keywords: | Maxi-chloride channel HT-29 intestinal epithelium electrolyte transport Ca2+-ionophore |
| 本文献已被 SpringerLink 等数据库收录！ |
|
