Figure 6.

Hydrogen peroxide induces afterdepolarizations in CMLCs. Shown are representative responses of isolated CMLCs and atrial myocytes to a train of current pulses delivered at 1-Hz in (A) 10 μmol/L hydrogen peroxide and (B) at baseline. In both (A) and (B), the top trace is from a Dct-null CMLC, the middle trace is from a Dct-het CMLC and the bottom trace is from a Dct-null atrial myocyte. In the presence of hydrogen peroxide there are increased early afterdepolarizations (black arrowheads) and delayed afterdepolarizations (green arrowheads) in each cell exposed to hydrogen peroxide compared to baseline. The black dash to the left of each trace represents the zero potential mark, and the solid horizontal line denotes the last six pulses of the 1-Hz train in both panels.