Table 1.
ED50 values (95% CL) in mg/kg for individual drugs in the von Frey test, Hargreaves’ test, and on food-maintained schedule-controlled responding. For drug combinations, only the ED50 values of the I2 receptor ligands are presented.
| Treatment | von Frey | Hargreaves | Operant Responding | |
|---|---|---|---|---|
| 2-BFI | 7.1 (5.7, 8.8) | 10.0 (7.6, 13.2) | 9.9 (8.2, 11.8) | |
| Phenyzoline | 43.5 (33.7, 56.2) | 72.7 (53.4, 98.9) | 64.1 (51.1, 80.4) | |
| Acetaminophen | 100.8 (83.1, 122.3) | 131.9 (95.9, 181.3) | 261.7 (214.4, 319.3) | |
|
| ||||
| 2-BFI/Acetaminophen | von Frey ratios | Hargreaves ratios | ||
|
| ||||
| 1:3 | 2.1 (1.3, 3.1) | 4.2 (3.2, 5.7) | 2.8 (2.3, 3.4) | 1.6 (1.2, 2.2) |
| 1:1 | 5.7 (4.7, 7.7) | 6.9 (5.3, 9.1) | 3.7 (2.8, 5.0) | 2.7 (2.2, 3.4) |
| 3:1 | 8.8 (6.6, 11.7) | 10.8 (6.5, 17.9) | 3.0 (2.4, 3.8) | 1.7 (1.1, 2.8) |
|
| ||||
| Phenyzoline/acetaminophen | ||||
|
| ||||
| 1:3 | 7.4 (4.7, 11.7) | 22.0 (12.4, 38.9) | 8.0 (6.6, 9.7) | 5.9 (4.6, 7.5) |
| 1:1 | 20.8 (11.1, 39.1) | 25.0 (7.9, 78.7) | 10.0 (8.1, 12.3) | 7.3 (4.4, 12.3) |
| 3:1 | 18.6 (12.4, 27.9) | 50.7 (40.2, 63.9) | 11.3 (8.5, 15.1) | 18.7 (13.6, 25.5) |