ED50 (95% CI) values for i.t. morphine in the tail flick test in CD-1 mice
| Morphine ED50 (95% CI) | |
|---|---|
| μg | |
| Control | 0.07 (0.04–0.12) |
| +IL1β i.c.v. | 0.37 (0.21–0.65)1-a |
| + IL1βi.c.v. + IL1β antiserum i.c.v. | 0.07 (0.03–0.14) |
| +Dyn i.t. | 0.71 (0.52–0.97)1-a |
| + Dyn i.t. + IL1β antiserum i.c.v. | 0.08 (0.03–0.18) |
Morphine was given i.t. at four or more dose levels to all groups ( n = 7–8 mice) 5 min before the tail flick test in control mice or those treated with IL1β (i.c.v., 10 ng, 5 min) or Dyn (i.t., 10 pg, 5 min) alone or along with IL1βantibody (i.c.v., 4 ng, 1 h).
CI, confidence interval.
↵1-a Significant difference from control morphine group ( p ≤ 0.05) by potency ratio method (Lichfield and Wilcoxon, 1949).