Fig. 5.
CMPI and dFBr act independently to potentiate low-sensitivity (α4)3(β2)2 nAChRs. (A and B) Representative current responses elicited by 10 µM ACh (A) or 1000 µM ACh (B) in the absence and presence of CMPI and/or dFBr. (C) ACh concentration response in the absence (△) and presence of 1 µM CMPI and 1 µM dFBr (▪). For each ACh concentration (−/+ drug), the current was normalized to the current elicited by 1000 µM ACh in the same oocyte. Average (±S.E.) from multiple oocytes [△ (9), ▪ (8)] were plotted and fit to eq. 1. Values of ACh (EC50/n/Imax) were as follows: ACh (control), 106 ± 29 μM/0.62 ± 0.06/124 ± 7%; ACh (+CMPI+dFBr), 0.20 ± 0.04 μM/1.2 ± 0.3/223 ± 8%.