Table 2.
Geometric Mean EC50 and IC50 values for agonist-induced responses of the LM/MP from animals implanted with morphine or placebo pellets for various times.
| Days following implantation | NICOTINE EC50 (−Log M) |
DAMGO IC50 (−Log M) |
2-CADO IC50 (−Log M) |
||||||
|---|---|---|---|---|---|---|---|---|---|
| Placebo | Morphine | Ratio | Placebo | Morphine | Ratio | Placebo | Morphine | Ratio | |
| 1 | 6.07 (±0.21) | 5.94 (±0.14) | 1.34 | 8.11 (±0.15) | 7.79 (±0.09) | 2.08 | 7.27 (±0.06) | 7.04* (±0.11) | 1.69 |
| 4 | 6.05 (±0.23) | 6.15 (±0.14) | 0.79 | 7.96 (±0.07) | 7.36* (±0.08) | 3.98* | 7.16 (±0.08) | 6.65* (±0.06) | 3.23* |
| 7 | 5.90 (±0.16) | 5.98 (±0.21) | 0.83 | 8.03 (±0.09) | 7.17* (±0.11) | 7.24* | 7.1 (±0.05) | 6.32* (±0.07) | 6.02* |
| 10 | 6.23 (±0.24) | 5.99 (±0.19) | 1.74 | 7.61 (±0.13) | 7.09* (±0.04) | 3.31* | 7.12 (±0.05) | 6.23* (±0.10) | 7.76* |
| 14 | 6.01 (±0.21) | 6.03 (±0.20) | 0.95 | 7.74 (±0.09) | 7.36 (±0.07) | 2.40 | 6.88 (±0.11) | 6.27* (±0.08) | 4.07* |
Sample sizes were 4 for each group at each time period.
Values that are significantly different from placebo (p ≤ 0.05) are indicated by *.