Table 1.
Binding affinities and antinociceptive potencies of the phosphopeptides.
| Peptide | Ki (nM ± S.E.) | Ratio | A50 (95% CI) | |||
|---|---|---|---|---|---|---|
| [3H]DAMGO MOR | [3H]Naltrindole DOR | [3H]U69,593 KOR | MOR:DOR: KOR | i.c.v. (nmol/mouse) | i.v. (μmol/kg) | |
| 1 | 1.4 ± 0.08 | 4.1 ± 0.41 | 34 ± 2.2 | 1:3:15 | 0.068 (0.054–0.086) | 46.4 (35.4–60.7) |
| 1a | 3.9 ± 0.19 | 7.9 ± 0.73 | 310 ± 66 | 1:2:79 | 0.34 (0.22–0.52) | 54.1 (48.5–60.2) |
| 1b | 8.7 ± 0.93 | 3.3 ± 0.33 | 130 ± 6.2 | 3:1:39 | 0.093 (0.053–0.16) | 30% @ 32.0 mg/Kg |
| 1c | 2.4 ± 0.017 | 7.0 ± 1.2 | 49 ± 4.3 | 1:3:20 | 0.02 (0.01–0.04) | 11.4 (8.5–15.2) |
| 2 | 0.68 ± 0.2 | 600 ± 44 | 190 ± 9.3 | 1:880:220 | 0.002 (0.0015–0.003) | 0.135 (0.106–0.172) |
| 2a | 3.8 ± 0.73 | 1400 ± 180 | 31% inhib. @ 10 μM | 1:370:>1000 | 0.042 (0.02–0.07) | 1.5 (1.3–1.8) |
| 2b | 4.2 ± 0.34 | 55 ± 4.6 | 570 ± 9.8 | 1:13:140 | 0.033 (0.02–0.05) | 30% @ 38.1 mg/Kg |
| 2c¶ | 1.3 ± 0.14 | 54% inhib. @ 10 μM | 270 ± 2.5 | 1:>7000:208 | 0.019 (0.012–0.029) | 0.602 (0.470–0.772) |
¶
Values are taken from Lowery et al.12
Peptides were incubated with membranes from CHO cell expressing human opioid receptors. Analgesic potency was evaluated i.c.v. and i.v. in mice. Details are provided in the experimental section.