Abstract: The present invention is directed to multiple-peptide channel assemblies for transport of anions such as chloride ions through epithelial cells, synthetic peptides capable of forming such channel assemblies and methods for using channel assemblies in therapeutic contexts for altering the flux of water across epithelial cells. The channel assemblies are composed of a plurality of peptides that transport through the membrane of an epithelial cell and provide for alteration of the flux of water through the cell. The peptides are soluble in water to a level of at least 10 mM and exhibit at least about 50% helical content when dispersed in a 40% trifluoroethanol/60% water solution. The peptides ideally have the amino acid sequence ABC(X).sub.