Figure 6

Inhibitory effect of CBN on erg-mediated K⁺ current (I_K(erg)) identified in GH₃ cells. In these experiments, we immersed cells in high-K⁺, Ca²⁺-free solution, and we filled up the pipet using K⁺-containing solution. (A) Representative current traces obtained in the absence (upper) and presence (lower) of 10 µM CBN. Inset in the upper panel shows the voltage-clamp protocol applied. (B) Mean I-V relationship of peak I_K(erg) (filled squares) and late I_K(erg) (open circles) recorded from these cells (mean ± SEM; n = 8 for each point). The upper or lower panel depicts the I-V relationship of the current in the absence (blue color) or presence (red color) of 10 µM CBN, respectively. Current amplitude (peak or late component) was measured at the start or the end of 1-s hyperpolarizing pulse from −10 mV to various voltage steps ranging between −100 and −20 mV in 10-mV step.