several controversial areas are considered , including the extent of cell swelling as water flows across the epithelium from dilute apical solution to isotonic basal solution , whether only principal cells or principal cells and intercalated cells participate in the water permeability response of the collecting duct , the role of the cytoskeleton in the water permeability response , and the proposed second water permeability barrier that is affected by adh , but not by adenosine 3',5'-cyclic monophosphate .
C0007634
cells
C0010853
cytoskeleton