TABLE 1

Inhibition of [3H]DASB and [3H]S-citalopram binding to hSERT by 5-HT and SERT inhibitors Assay concentrations of [3H]DASB and [3H]S-citalopram were 0.5 and 1 nM, respectively. Observed IC50 values for each test compound, obtained by nonlinear regression of the concentration binding data, were converted to equilibrium binding affinities using the Cheng-Prusoff equation, under the assumption that the binding interactions were competitive. Hill slopes and Ki values obtained for different inhibitors (n = 2–4) are presented as mean ± standard deviation. For these analyses, the equilibrium binding affinities of the radioligands, Kd values, were determined from separate analyses (see Fig. 1) and were found to be 0.14 and 1.2 nM, respectively, for [3H]DASB and [3H]S-citalopram.


Radioligand

Inhibitor

Ki

Hill Slope

n
nM
[3H]DASB 5-HT 3100 ± 521 0.94 ± 0.10 4
DASB 0.065 ± 0.02 0.93 ± 0.15 5
S-Citalopram 1.33 ± 0.72 1.04 ± 0.25 4
R-Citalopram 42 ± 22 1.21 ± 0.33 4
Paroxetine 0.035 ± 0.005 1.16 ± 0.10 4
Clomipramine 0.09 ± 0.01 1.02 ± 0.21 3
Fluvoxamine 6.7 ± 0.8 0.94 ± 0.18 4
Imipramine 3.54 ± 0.55 0.98 ± 0.11 4
Duloxetine 0.06 ± 0.04 1.05 ± 0.30 4
Venlafaxine 16.6 ± 2.98 1.03 ± 0.13 4
β-CIT 0.21 ± 0.05 1.11 ± 0.13 3
Indatraline 0.23 ± 0.13 1.03 ± 0.05 4
Cocaine 210 ± 96 0.73 ± 0.05 2
[3H]S-Citalopram 5-HT 1700 ± 390 1.06 ± 0.11 3
DASB 0.097 ± 0.06 0.94 ± 0.28 2
S-Citalopram 0.79 ± 0.13 1.06 ± 0.22 4
Imipramine 1.5 ± 0.30 1.04 ± 0.06 3
Duloxetine 0.093 ± 0.015 1.21 ± 0.05 3

Venlafaxine
16.3 ± 7.8
0.96 ± 0.18
2