Figure 4. Pharmacological dissection of K_IR and K_ATP currents in mesenteric VSMCs.

A, K_IR currents were defined as the fraction of current sensitive to 100 μm BaCl₂ (dif), and were obtained by subtracting current traces elicited by voltage ramps in the presence of BaCl₂ (Ba) from traces in control conditions (C). Sample traces obtained with VSMCs from BPN and BPH mice using the perforated patch configuration are shown in the left panels. The K_IR average current densities obtained at −150 mV, both with the perforated patch (pp) or the whole-cell configuration (wc) of the patch clamp technique, are depicted in the bar plot. B, K_ATP currents were defined as the difference (dif) between currents recorded in the presence of 100 μm pinacidil (Pin) and currents recorded in the presence of 20 μm glibenclamide (Gli). Current–voltage plots show representative traces obtained with the perforated patch configuration, and bar graphs depict the K_ATP average current densities obtained at −150 mV. Each bar, in both A and B, is the mean ± SEM of 7–10 cells. *P < 0.05, **P < 0.01.