Fig. 3.

Effect of La³⁺ on the resting membrane potential of Cx50^−/− fiber cells. A: representative current responses to a voltage-clamp ramp protocol in the presence of 0 Ca²⁺, 2 Mg²⁺ (black current trace); 1 Ca²⁺, 1 Mg²⁺(red current trace); or 1 Ca²⁺, 1 Mg²⁺, 1 La³⁺(blue current trace). Smooth lines are exponential fits of the current response to determine the resting potential. B: plot summarizing the resting potential data determined using the voltage-ramp protocol shown in A after correction for liquid junction potential. Data are means ± SE (n = 12). *P < 0.001, compared with fiber cells treated with 1 mM La³⁺ by student's t-test.