Relative affinities (K i) of opioid receptor selective agonists and antagonists in CHO cells expressing DOR-1, MOR-1, or various opioid receptor chimers
| Receptor Type | Ki | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| DPDPE | Deltorphin I | NTB | TIPPψ | DAMGO | PL017 | Oxymorphone | Naloxone | CTOP | |
| nM | |||||||||
| DOR-1 (δ) | 2.9 ± 0.41 | 5.5 ± 1.9 | 0.81 ± 0.14 | 1.9 ± 0.37 | 2900 ± 550 | >10,000 | 250 ± 93 | 130 ± 28 | >10,000 |
| μ1δ | 25 ± 18 | 70 ± 37 | 0.93 ± 0.39 | 3.7 ± 0.70 | 360 ± 180 | >10,000 | 55 ± 20 | 12 ± 2.7 | >10,000 |
| μ12δ | 4.0 ± 0.61 | 4.0 ± 0.79 | 0.10 ± 0.08 | 3.2 ± 0.35 | 340 ± 220 | >10,000 | 32 ± 4.8 | 26 ± 4.8 | >10,000 |
| μ1–3δ | 7.8 ± 1.1 | 19 ± 4.8 | 0.50 ± 0.05 | 16 ± 2.3 | 66 ± 15 | >10,000 | 49 ± 8.4 | 23 ± 4.1 | 22 ± 6.5 |
| μ1–4δ | 4.3 ± 1.5 | 12 ± 1.6 | 0.068 ± 0.01 | 54 ± 9.1 | 71 ± 18 | 910 ± 130 | 8.1 ± 1.4 | 99 ± 31 | 66 ± 19 |
| μ1–5δ | 5.4 ± 3.9 | 8.5 ± 5.1 | 0.26 ± 0.07 | 13 ± 2.6 | 1.3 ± 0.3 | 110 ± 21 | 1.8 ± 0.41 | 2.0 ± 0.77 | 120 ± 41 |
| δ1μ | 49 ± 19 | 32 ± 1.6 | 0.16 ± 0.05 | 6.7 ± 1.5 | 22 ± 3.5 | 400 ± 150 | 68 ± 12 | 3.3 ± 0.38 | 18 ± 1.8 |
| δ1–3μ | 1200 ± 610 | 700 ± 280 | 12 ± 2.5 | >10,000 | 15 ± 4.6 | 640 ± 91 | 3.9 ± 2.3 | 3.9 ± 2.1 | >10,000 |
| δ1–4μ | 3000 ± 1900 | >10,000 | 21 ± 8.8 | >10,000 | 140 ± 60 | 170 ± 61 | 0.39 ± 0.30 | 9.5 ± 2.8 | >10,000 |
| δ1–5μ | 360 ± 130 | 250 ± 52 | 14 ± 2.0 | >10,000 | 85 ± 24 | >10,000 | 14 ± 3.7 | 6.8 ± 1.1 | >10,000 |
| δ1–6μ | 12 ± 7.3 | 29 ± 16 | 0.68 ± 0.19 | 12 ± 1.4 | 350 ± 130 | >10,000 | 73 ± 10 | 0.38 ± 0.15 | >10,000 |
| δ456μ | 14 ± 2.9 | 22 ± 2.5 | 0.10 ± 0.005 | 5.8 ± 0.77 | 8.9 ± 2.5 | 370 ± 72 | 35 ± 4.2 | 1.2 ± 0.11 | 11 ± 0.89 |
| δ45μ | 13 ± 5.4 | 17 ± 3.1 | 0.18 ± 0.019 | 16 ± 2.3 | 35 ± 6.9 | 3300 ± 2600 | 47 ± 3.6 | 2.8 ± 0.26 | 16 ± 1.2 |
| δ56μ | 41 ± 17 | 59 ± 17 | 0.03 ± 0.005 | 120 ± 31 | 250 ± 45 | 3900 ± 2300 | 190 ± 41 | 3.6 ± 0.25 | 44 ± 6.7 |
| δ5μ | 34 ± 9.7 | 11 ± 2.7 | 0.03 ± 0.004 | 79 ± 15 | 79 ± 15 | 3400 ± 840 | 150 ± 15 | 3.7 ± 0.36 | 55 ± 14 |
| MOR-1 (μ) | 160 ± 63 | >10,000 | 12 ± 1.3 | >10,000 | 1.6 ± 0.35 | 6.2 ± 1.4 | 0.82 ± 0.24 | 3.5 ± 0.44 | 0.96 ± 0.31 |
Relative affinities of various opioid agonists and antagonists in CHO cells stably expressing DOR-1, MOR-1, or receptor chimeras were determined by competition binding assays using [3H]diprenorphine as radioactive ligand. IC50 values of ligands were obtained from computer analysis of competition curves using Sigma Plot. K i values were then calculated using the Cheng-Prusoff equation.