Values are mean ± S.E. from three or four (a) experiments. The competing radioligand was [3H]QNB. The Hill coefficients ranged from 0.8 to 1.2, with the exception of benzilylcholine, which showed approximately 20% of low-affinity sites (see Experimental Procedures).
1-b Fitting data to the Hill equation gave a Hill coefficient of less than 0.7. The result shown is the value for the high-affinity site obtained from fitting the data to a two-site model of ligand binding.