Fig. 1.

Total specific [¹²⁵I]epibatidine binding in total membranes prepared from hippocampus and diencephalon cultures treated with nicotine for 96 h. Primary cultures of hippocampus (○) or diencephalon (●) were treated with nicotine concentrations of 0, 0.01, 0.1, 1, and 10 μM for 96 h. Binding was measured by using 200 pM [¹²⁵I]epibatidine in a 2-h binding reaction. Nonspecific binding was determined by including 100 μM cytisine in the binding reaction. A, total specific [¹²⁵I]epibatidine binding to the total membrane fractions prepared from the cultures. B, binding data transformed to percentage of control. Data represent mean ± S.E.M. of seven replicates from three independent experiments. Significant differences with respect to control (untreated) neurons were calculated by using one-way ANOVA, followed by Student-Newman-Keuls post hoc analysis. *, p < 0.001.