Fig. 1. Differential expression of Maxi-Cl channel activity between mouse mammary C127 cells and neuroblastoma C1300 cells. A. Maxi-Cl currents recorded in excised inside-out patches from C127 cells, but not from C1300 cells, upon application of an alternating pulse from 0 to ±25 mV (protocol is shown at the top of the traces). In C1300 cells, even after treatment with 10 μM tamoxifen (10 min) added to the bath (intracellular) and the pipette (extracellular) solution to mimic conditions previously reported to activate large-conductance anion channel currents in C1300 cells [22]. B. Mean patch currents recorded from C127 cells and C1300 cells in the absence and presence of tamoxifen. Each column represents the mean ± SEM (vertical bar).