Influence of Endogenous Cardiac Glycosides, Digoxin, and Marinobufagenin in the Physiology of Epithelial Cells

Figure 1

Digoxin and marinobufagenin enhance Gap junctional intercellular communication (GJIC) in MDCK cells in mature monolayers. (a) Effect of digoxin. (b) Effect of marinobufagenin on the CIGJ. Both figures show, in the upper part, a set of representative images, one for each one of the different concentrations tested. Multiple cell staining results from injection of a cell with Lucifer Yellow (green) which then diffuses to their neighbors through gap junction. Samples were counterstained with propidium iodide (red) to reveal the presence of nuclei in noninjected and injected cells. The histogram, in the bottom, part compares the average number of cells stained by injection, of a single cell, with Lucifer Yellow. (c) In the left part, a set of representative dye injection trials made in monolayers treated with either digoxin (100 nM) or marinobufagenin (10 nM) in the absence or presence of 1 mM octanol. The right part compares the average number of stained cells in the presence or absence of octanol. Numbers above each bar indicate the number of trials. The asterisks indicate a statistically significant difference compared to the 0 nM group (Dunn’s method); p ≤ 0.05, p ≤ 0.001.

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