Figure 5.

Effects of i.v. injections of O-4394 (n=6–10; left-hand panels) and O-4395 (n=6–11; right-hand panels) on (a) anti-nociception at +20 min, (b) ring immobility at +40 min and (c) hypothermia at +60 min in mice. Each column represents the mean value and vertical lines show s.e.m. In some experiments, injection of O-4394 or O-4395 at 56 mg kg⁻¹ i.v. was preceded at −10 min by an i.p. injection of 3 mg kg⁻¹ SR141716A (solid columns). %MPE is the percentage of maximum possible effect in the tail-flick test. Asterisks denote significant differences between the effects of vehicle (V) and O-4394 or O-4395 (^*P<0.05; ^**P<0.01; ^***P<0.001; ANOVA followed by Fisher's PLSD test) and the symbol # denotes significant differences between responses to O-4394 or O-4395 alone at 56 mg kg⁻¹ i.v. and responses to this dose of O-4394 or O-4395 following pretreatment with SR141716A (P<0.05; ANOVA followed by Fisher's PLSD test). Mean antinociceptive ED₅₀ values with 95% confidence limits shown in parentheses were 43 mg kg⁻¹ (22 and 83 mg kg⁻¹) for O-4394 and 44 mg kg⁻¹ (23 and 82 mg kg⁻¹) for O-4395.