Figure 2.

Detection of ACh- and nicotine-induced currents in cultured BECs. (A, a) ACh (100 μM) induced a rapid inward current in BEC. (A, b) Mecamylamine (Mec; 25 μM) was perfused for 3–5 minutes, then 100 μM ACh plus 25 μM mecamylamine was applied and resulted in a diminished ACh-induced inward current. (A, c) The ACh (100 μM) induced current after washout of mecamylamine. All traces are from the same cell. Holding potential was −60 mV. (B) Inward currents in response to application of nicotine at concentrations shown. (C) Dose–response of BEC response to nicotine. Peak currents evoked at concentrations shown are expressed relative to the peak current evoked by 100 μM of nicotine and plotted against the log of nicotine concentration. Mean response was taken from 5–12 cells. Experimental data were fitted to the Hill equation (EC₅₀ = 26.5 μM; Hill coefficient = 1.0). Data are presented as means (±SEM).