Table 1.
KI values for displacement of β-CIT from wild-type SERT
| NaCl | Na-Ise | NMDG-Cl | NMDG-diatrizoate | |
|---|---|---|---|---|
| β-CIT | 0.6 ± 0.2 | 0.6 ± 0.2 | 2.6 ± 0.4* | 2.5 ± 0.8* |
| Cocaine | 486 ± 44 | 405 ± 27 | 1657 ± 47* | ND |
| Paroxetine | 2.0 ± 0.4 | 2.0 ± 0.8 | 6.4 ± 1.1* | ND |
| Imipramine | 61 ± 4 | 221 ± 13* | 296 ± 36* | 518 ± 69* |
| Fluoxetine | 13 ± 1 | 38 ± 0.8* | 48 ± 3* | 66 ± 8* |
| Sertraline | 4.2 ± 0.7 | 7.0 ± 1.3* | 30 ± 3* | ND |
| Citalopram | 3.1 ± 0.5 | 10.5 ± 3.2* | 16 ± 2* | ND |
| Ibogaine | 3402 ± 387 | 2592 ± 518 | 1112 ± 213* | ND |
Displacement of β-CIT binding from wild-type rSERT was performed as described for Figure 1 under four ionic conditions [NaCl, Na-isethionate (Na-Ise), NMDG-Cl, and NMDG-diatrizoate]. KD values (in bold) (in nanomolar concentrations) were calculated for β-CIT binding and were used to determine KI values (in nanomolar concentrations) of the other inhibitors using the Cheng–Prusoff equation (Cheng and Prusoff, 1973). ND, Not determined. Statistical analysis from three or four independent experiments (2 for Na+ dependences published previously; paroxetine, fluoxetine, and citalopram in NMDG-Cl) was performed in Origin8 using one-way ANOVA, followed by Tukey's multiple comparisons test.
*p < 0.03, statistically significant differences between affinities in NaCl versus the other ionic condition. The difference between NMDG-Cl and NMDG-diatrizoate was statistically significant for imipramine (p = 0.006) but not for fluoxetine (p = 0.06).