Fig. 2.

Rb⁺ flux assays of HEK 293 cells transiently and stably expressing Kir2.1Y channel. (a and b) In Rb⁺ influx (a) and efflux (b), 293 cells were transiently transfected with Kir2.1Y expression vector (▪)or empty vector (•). Data obtained with 2.5 mM MTSET treatments are shown as □ or ○. (c) Rb⁺ efflux of 293 cells stably expressing Kir2.1Y channel with (□) or without (▪) MTSET treatment were measured. (d and e) Determination of MTSET treatment conditions. (d) Rb⁺ efflux (%) of 293 cells stably expressing Kir2.1Y channel (filled bars) and mock 293 cells (open bars) were quantified after being treated in triplicates with 5 mM MTSET for 0, 2.5, 5 and 10 min at room temperature. (e)Rb⁺ efflux (%) of 293 cells stably expressing Kir2.1Y channel (filled bars) and mock 293 cells (open bars) were quantified after being treated in duplicate with 0, 0.5, 1, 2.5 and 5 mM MTSET for 5 min at room temperature.