TABLE 1.
ED50 values (in milligrams per kilogram) for effects of agonists on food-reinforced responding in pigeons at different injection-test intervals and pA2 values of CGP35348 [in – log (mol/kg)] to antagonize these effects Numbers in parentheses are the 95% confidence limits.
|
Agonist
|
Time
|
CGP35348
|
pA2
|
|||
|---|---|---|---|---|---|---|
| 0 | 3.2 | 10 | 32 | |||
| min | mg/kg | |||||
| Baclofen | 30 | 9.4 (7.4–12) | 14 (10–N.D.) | 22 (16–30) | 33 (24–47) | 4.46 (4.10–4.82) |
| 60 | 8.6 (7.1–10) | 15 (12–N.D.) | 18 (14–22) | 31 (25–40) | 4.49 (3.93–5.05) | |
| 120 | 9.1 (7.9–10) | 14 (12–17) | 19 (16–22) | 34 (28–40) | 4.46 (4.07–4.85) | |
| 240 | 12 (9.6–15) | 17 (13–N.D.) | 22 (17–28) | 36 (27–48) | 4.34 (3.95–4.73) | |
| SKF97541 | 15 | 0.077 (0.047–0.14) | 0.12 (0.068–N.D.) | 0.19 (N.D.) | 0.42 (0.20–N.D.) | 4.46 (4.11–4.81) |
| 30 | 0.046 (0.034–0.063) | 0.079 (0.057–0.11) | 0.15 (N.D.) | 0.20 (0.14–0.30) | 4.63 (4.17–5.09) | |
| 60 | 0.046 (0.036–0.059) | 0.078 (0.061–0.098) | 0.11 (0.085–0.15) | 0.18 (0.14–0.24) | 4.54 (4.09–4.98) | |
| 120 | 0.051 (0.041–0.064) | 0.079 (0.064–0.098) | 0.11 (0.085–0.14) | 0.22 (N.D.-30) | 4.52 (4.21–4.82) | |
| 240 | 0.091 (0.067–0.13) | 0.10 (0.074–0.16) | 0.15 (0.10–N.D.) | 0.30 (0.18–N.D.) | 4.18 (3.92–4.43) | |
| GHB | 15 | 150 (120–190) | 200 (160–250) | 250 (190–N.D.) | 250 (190–N.D.) | 4.14 (3.26–5.02) |
| 30 | 150 (130–180) | 170 (140–200) | 240 (210–270) | 260 (220–N.D.) | 3.97 (3.47–4.47) | |
| 60 | 160 (130–200) | 180 (150–210) | 280 (230–N.D.) | 340 (280–400) | 3.96 (2.38–5.54) | |
| GBL | 30 | 79 (67–93) | 100 (82–130) | 94 (76–120) | 130 (N.D.-170) | 3.91 (2.98–4.85) |
| 60 | 100 (81–130) | 110 (86–140) | 140 (130–150) | 150 (120–N.D.) | 3.72 (3.24–4.19) | |
N.D., not determined because the confidence limit could not be calculated