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

Figure 4

L-type Ca²⁺ and outward K⁺ currents recorded from the ventricular cells of control and H/M-Sod2 ^−/− mice and influences of chronic AP intake. (a) Representative current traces of the L-type Ca²⁺ current recorded from the left ventricular cells of each group. (b) Densities of the L-type Ca²⁺ current of the left ventricular cells of each group. Values are mean ± SEM, control, 𝑛=4; control + AP, 𝑛=7; H/M-Sod2 ^−/−, 𝑛=16; and H/M-Sod2 ^−/− + AP, 𝑛=9. (c) Representative current traces of the outward K⁺ current recorded from the left ventricular cells of each group. (d) Densities of the peak outward K⁺ current (𝐼_peak) of the left ventricular cells of each group. 𝐼_peak was measured 2 ms after a 300 ms voltage step to +60 mV. (e) Densities of the steady state K⁺ current (𝐼_ss) of the left ventricular cells of each group. 𝐼_ss was measured at the end of a 300 ms voltage step to +60 mV. Control, 𝑛=32; control + AP, 𝑛=31; H/M-Sod2 ^−/−, 𝑛=32; and H/M-Sod2 ^−/− + AP, 𝑛=32.

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