Figure 5. CO₂-dependent dye loading into the connexin-expressing HeLa cells.

An increase of from 35 mmHg to 70 mmHg causes a large significant increase in dye loading for cells expressing Cx26 and Cx32. Cells expressing Cx30 show a smaller increase that failed to achieve statistical significance. Cx36 showed no change in dye loading, while Cx43 showed a decrease in loading. All connexin-expressing cells demonstrated increased loading of carboxyfluorescein under control conditions, whereas the wild-type cells showed no loading under the control or elevated CO₂ conditions (yellow panels: bright field images of WT cells). Scale bar 20 μm. Statistical comparison of change in loading at 70 mmHg versus that at 35 mmHg by Mann–Witney U test, P values given where this difference was significant.