Figure 3.

Ouabain treatment under sodium-free conditions does not affect the formation of tight junctions and desmosomes. A and B and C and D are the immunofluorescence localization of ZO-1 and desmocollin, respectively. Note the comparable staining pattern in control (A and C) and ouabain-treated (B and D) cells. (E) Measurement of TER. (F and G) Transmission electron micrographs of control (F) and ouabain-treated (G) cells show tight junctions (arrow) and desmosomes (asterisk). Insets are the higher magnification of the tight junction region in F and G. (H–K) Confocal microscope X-Z sections. Note the polarized distribution of β-catenin and GP135 in control and ouabain-treated cells. Bars in A–D, 10 μm; F and G, 500 nm and 1 μm, respectively; and H–K, 5 μm.