Cardiac Electrophysiological Alterations in Heart/Muscle-Specific Manganese-Superoxide Dismutase-Deficient Mice: Prevention by a Dietary Antioxidant Polyphenol

Figure 5

The inward rectifier K⁺ current (𝐼_K1) recorded from the ventricular cells of control and H/M-Sod2 ^−/− mice and influences of chronic AP intake. (a) Representative traces of 𝐼_K1 recorded from the left ventricular cells of each group. (b) Densities of 𝐼_K1 of the left ventricular cells of each group. The density of 𝐼_K1 was measured at the end of a hyperpolarizing pulse to –50 mV from a holding potential of –40 mV. Note that the density of 𝐼_K1 in H/M-Sod2 ^−/− ventricular cells was significantly smaller than that in control cells and that the reduction in 𝐼_K1 density in H/M-Sod2 ^−/− cells was improved by chronic AP intake. Values are mean ± SEM, control, 𝑛=32; control + AP, 𝑛=31; H/M-Sod2 ^−/−, 𝑛=32; and H/M-Sod2 ^−/− + AP, 𝑛=32. Differences between groups, *𝑃<0.05.

(a)

(b)