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.

CompoundKi Value
DATσ1σ2
mM
WIN 35,4285.24 (4.92–5.57)a5700 (4060–8020)4160 (3120–5550)
SH 3-2412.2 (10.8–13.8)22.9 (18.5–28.2)20.0 (15.7–25.6)
Nomifensine21.0 (18.9–23.3)8240 (5360–12,700)65,200 (54,300–78,300)
Methylphenidate65.8 (61.2–70.8)6780 (4520–10,200)37,400 (21,200–66,100)
Cocaineb76.6 (72.6–80.5)5190 (3800–7060)19,300 (16,000–23,300)
Rimcazole96.6 (77.3–121)883 (661–1180)238 (171–329)
SH 3-28188 (166–213)19.0 (15.3–23.6)47.2 (40.4–55.2)
AC9271,930 (1610–2320)53.1 (45.6–61.8)78.9 (48.2–129)
BD 1008b2,510 (2250–2790)2.13 (1.77–2.56)16.6 (13.0–21.1)
BD 1047b3,220 (2820–3670)3.13 (2.68–3.65)47.5 (36.7–61.4)
NE-1003,590 (3,210–4,000)2.48 (2.13–2.88)121 (91.9–159)
BD 1063b8,020 (7100–9060)8.81 (7.15–10.9)625 (447–877)
  • a The value for affinity of WIN 35,428 at the DAT is a Kd value obtained from a homologous competition study.

  • b 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.