Effects of the EK mutation on Ca
1.1 currents, ECC, and ECCE. Voltage dependence of peak CaV1.1 current density for FDB fibers from (A) WT mice (n = 5) and (B) EK mice (n = 9). (C and D) Representative traces of electrically-evoked mag-fluo-4 transients in FDB fibers obtained from (C) WT and (D) EK mice. Insets: The first transient for each condition on an expanded time scale in FDB fibers obtained from WT and EK mice. (E) Average amplitude and (F) decay constant of the recovery phase in FDB fibers from WT and EK mice. (G) Representative Mn2+ quench of fura-2 fluorescence in myotubes from WT and EK mice. (H) Average rate of Mn2+ quench in myotubes from WT and EK mice. (I) Scheme of ECC changes altered in EK muscle. Data are shown as mean ± SEM. **P <0.01 and ***P <0.001.