Table 3 Competition of [3H] DAMGO binding among the rat MOR-1 variants
Ligand | K i Value | |||||
|---|---|---|---|---|---|---|
| Â | 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 |