Fig. 1. Comparisons of the time courses of acetylcholine current responses of human neuronal nicotinic acetylcholine receptor (hnAChR) in ND96 and calcium-free Ba2+–Ringer's solution (Ba-R). Each current response was normalized to the peak current response during application of EC30concentrations of acetylcholine for 60 s. Error bars are smaller than the symbols for some values; n = 4–6.