Figure 2.

Time course of the antinociceptive effect of daily administration of intrathecal morphine (15 μg) alone and in combination with S(+) and R(−) ibuprofen (10 μg) in the (a) tailflick and (b) paw pressure tests. Morphine and the test agents were administered as a single dose. Nociceptive testing was performed 30 min following each injection. The data are presented as mean±s.e.mean for 5–7 animals. ^*Significant differences from the action of morphine (P<0.05); #Significant differences from the action of morphine/R(−) ibuprofen alone (P<0.05).