TABLE 1.
Inhibition by various compounds of specific binding to the DAT, σ1, or σ2 receptors
The values listed are Ki values ± S.E.M. (95% confidence limits), with the exception of the value for WIN 35,428 at the DAT, which is a Kd value obtained from a homologous competition study. See Materials and Methods for details of the assay procedures and derivation of Ki values.
| Compound |
Ki Value |
||
|---|---|---|---|
| DAT | σ1 | σ2 | |
| mM | |||
| WIN 35,428 | 5.24 (4.92–5.57)a | 5700 (4060–8020) | 4160 (3120–5550) |
| SH 3-24 | 12.2 (10.8–13.8) | 22.9 (18.5–28.2) | 20.0 (15.7–25.6) |
| Nomifensine | 21.0 (18.9–23.3) | 8240 (5360–12,700) | 65,200 (54,300–78,300) |
| Methylphenidate | 65.8 (61.2–70.8) | 6780 (4520–10,200) | 37,400 (21,200–66,100) |
| Cocaineb | 76.6 (72.6–80.5) | 5190 (3800–7060) | 19,300 (16,000–23,300) |
| Rimcazole | 96.6 (77.3–121) | 883 (661–1180) | 238 (171–329) |
| SH 3-28 | 188 (166–213) | 19.0 (15.3–23.6) | 47.2 (40.4–55.2) |
| AC927 | 1,930 (1610–2320) | 53.1 (45.6–61.8) | 78.9 (48.2–129) |
| BD 1008b | 2,510 (2250–2790) | 2.13 (1.77–2.56) | 16.6 (13.0–21.1) |
| BD 1047b | 3,220 (2820–3670) | 3.13 (2.68–3.65) | 47.5 (36.7–61.4) |
| NE-100 | 3,590 (3,210–4,000) | 2.48 (2.13–2.88) | 121 (91.9–159) |
| BD 1063b | 8,020 (7100–9060) | 8.81 (7.15–10.9) | 625 (447–877) |
The value for affinity of WIN 35,428 at the DAT is a Kd value obtained from a homologous competition study.
The values for these compounds are those reported in the literature by Garcés-Ramírez et al. (2010) using methods identical to those in the present study. For the [3H]DTG assay, the data typically modeled better for two than one binding site, and the Ki values for the higher affinity site are displayed in the table. The DTG high-affinity site is the site recognized as the σ2 receptor, whereas the low-affinity site is currently not identified. Values for the low-affinity DTG site (95% confidence limits) were as follows: SH 3-24, 12,700 (1300–124,000) nM; rimcazole, 25,900 (3620–185,000) nM; AC927, 55,200 (6860–444,000) nM; BD 1008, 20,500 (9640–43,500) nM; BD 1047, 55,300 (25,000–122,000) nM; and BD 1063, 53,700 (16,500–174,000) nM.