Fig. 4. Concentration-response curve for acetylcholine (ACh) current responses in oocytes expressing the human α3β4 nicotinic ACh receptor in the absence and presence of 150 μm succinylcholine (SuCh) (n = 5). Oocytes were first exposed to ACh and thereafter to 150 μm SuCh and ACh. Data were normalized to maximal ACh current within each oocyte. Data are presented as mean ± SEM.