Figure 8 of Dutot, Mol Vis 2008; 14:889-897.

Figure 8. Effects of extracellular Ca2+ and Mg2+ on YO-PRO-1 uptake. Both Ca2+ and Mg2+ decreased YO-PRO-1 uptake but Ca2+ has a more potent effect than Mg2+. Ca2+ and Mg2+ together have a synergic effect on the decrease in YO-PRO-1 uptake. The double asterisk indicates a p<0.01 compared to PBS and the triple asterisk denotes a p<0.001 compared to PBS.