Fig. 2.

La³⁺ blocks the Cx46 hemichannel current but not the potassium current. A: currents before and after the application of La³⁺ (1 mM) and the subtracted (La³⁺-sensitive) component recorded from a Cx50^−/− fiber cell. Dashed line represents zero current level. B: I–V relations obtained from the data shown in A. The current was measured at the end of the 8-second pulse and plotted as a function of voltage after correction for liquid junction potential. C: bar graph summarizing the La³⁺-sensitive current data at −60 mV in the presence of the indicated concentrations of Mg²⁺ and Ca²⁺. Data are means ± SE. Number of cells indicated by the values in parentheses. *P < 0.005, compared with the hypothesized population mean of 0.0 using the one-sample t-test.