Table 1

Inhibitory concentrations 50% (IC50) ± SE of receptorphin competition on different opioid sites, assayed by displacement binding of a variety of opioid ligands.

Opioid Source
DPDPE or DSLET
DAGO
EKC
Diprenorphin
EKC +DADLE
Diprenorphin +DADLE

MCF7
3.25 ± 0.42 × 10-9
1.43 ± 0.20 × 10-10
6.65 ± 1.01 × 10-11
5.78 ± 0.64 × 10-13
1.59 ± 0.14 × 10-10
>10-12
T47D
ND
ND
5.14 ± 0.74 × 10-10
>10-12
5.41 ± 0.57 × 10-11
>10-12
DU145
ND
6.52 ± 0.58 × 10-11
2.34 ± 0.55 × 10-11
ND
2.87 ± 0.22 × 10-11
ND
PC3
ND
4.30 ± 0.97 × 10-11
>10-6
ND
>10-6
ND
Rat
8.25 ± 0.81 × 10-8
1.81 ± 0.23 × 10-7
*1.85 ± 0.11 × 10-10
**5.77 ± 0.87 × 10-10
-
1.85 ± 0.43 × 10-10
Brain



2.65 ± 0.13 × 10-9



*[3H]U60-593 was used as a selective kappa1 opioid ligand **Displacement curves were best fitted with a two-site model. See text for details. IC50s (in Moles/L) were calculated by sigmoidal fitting of displacement experiments. ND = not detected. Mean ± SE of three different experiments performed in duplicate.

Kampa et al. BMC Pharmacology 2001 1:9   doi:10.1186/1471-2210-1-9