Fig. 2.

dFBr inhibition of muscle-type nAChRs. Xenopus oocytes expressing wild-type (A) human (2α:1β:1δ:1ε; ▽) or (B) Torpedo (2α:1β:1γ:1δ;▼) nAChR were voltage clamped at −50 mV, and currents elicited by 10 second applications of 10 µM ACh were recorded in the absence or presence of increasing concentrations of dFBr. Each drug concentration was tested at least three times and peak currents were normalized to the peak current elicited by 10 µM ACh alone. (C) Data (average ± S.E.) from at least three oocytes were plotted and fit to a single-site model (eq. 3); human nAChR, IC₅₀ = 1.0 ± 0.08 µM; Torpedo nAChR, IC₅₀ = 1.0 ± 0.06 µM.