|
Ligand
|
K
i
Value
|
|---|
| |
rMOR-1
|
rMOR-1H1
|
rMOR-1H2
|
rMOR-1i1
|
rMOR-1i2
|
rMOR-1i3
|
|
Morphine
|
1.5 ± 0.2
|
2.0 ± 0.3
|
0.8 ± 0.1
|
1.3 ± 0.4
|
1.2 ± 0.2
|
1.6 ± 0.2
|
|
M6G
|
4.5 ± 0.3
|
4.5 ± 0.5
|
2.6 ± 0.6
|
3.8 ± 0.5
|
5.1 ± 1.0
|
6.3 ± 0.7
|
|
DADLE
|
2.4 ± 0.1
| |
1.9 ± 0.3
| | | |
|
DSLET
|
6.3 ± 0.3
| |
7.2 ± 1.1
| | | |
|
Naloxone
|
0.8 ± 0.1
|
0.9 ± 0.1
|
0.8 ± 0.3
|
0.9 ± 0.1
|
0.7 ± 0.1
|
1.3 ± 0.2
|
|
β-Endorphin
|
2.7 ± 0.2
|
3.1 ± 0.3
|
3.8 ± 1.9
|
3.3 ± 0.3
|
3.7 ± 0.3
|
6.3 ± 0.7
|
|
Dynorphin A
|
15.5 ± 0.9
|
37.5 ± 5.3
|
21.8 ± 5.1
|
16.2 ± 3.5
|
23.6 ± 2.8
|
34.6 ± 6.8
|
|
U50,488H
|
> 500
|
> 500
|
> 500
|
> 500
|
> 500
|
> 500
|
|
DPDPE
|
> 500
|
> 500
|
> 500
|
> 500
|
> 500
|
> 500
|
- [3H] DAMGO binding was performed in membranes of CHO cells stably expressing the indicated variants. Dissociate constants, K
i
values, were determined from IC50 values of at least three independent determinations. One-way ANOVA was used to compare the K
i
values for each drug among the variants. Of the opioids, only M6G (p = 0.0157) showed significant difference with lower K
i
value of rMOR-1H2 as compared to that of rMOR-1i3 (p < 0.01) in Tukey post hoc analysis.
