Figure 2.

5-HT uptake kinetics in vehicle and PD169316-treated synaptosomes. Synaptosomes (50 μg) were preincubated with the vehicle or 10 μm PD169316 for 30 min at 37°C. After this treatment, uptake of 5-HT was measured over a concentration range of 0.01-1 μm using a 3 min uptake period. In parallel, nonspecific uptake at each concentration of 5-HT used (in the presence of 0.1 μm fluoxetine) was subtracted from total uptake to calculate SERT-mediated 5-HT uptake. Values are the averages from four independent experiments, and the mean values ± SEM are given. Nonlinear curve fits of data for uptake used the generalized Michaelis-Menten equation (Kaleidagraph). When not shown, error is contained within the symbol. The inset shows an Eadie-Hofstee plot of transformation of the data.