Fig. 7

Mutations of K504 affect conduction behaviour of Na⁺ substantially. a-c, e-i Representative currents recorded in Xenopus laevis oocytes two days after cRNA injection at indicated Na⁺ and K⁺ concentrations: Na03K0 - 0.3 mM NaCl without KCl, Na30K0 - 30 mM NaCl without KCl, Na30K1 - 30 mM NaCl and 1 mM KCl. A pulse at holding potential (zero current level) was followed by 1 s voltage pulses from +20 to -160 mV in -15 mV decrements and continued with a final pulse at holding potential for 1.5 s. d, j Mean current-voltage (IV) curves and standard deviation calculated from data obtained from three to six measurements