Figure 4.

Gabapentin does not produce antinociceptive effects against acute thermal and mechanical nociception in nonligated mice. Acute thermal and mechanical nociception were assessed by the plantar and paw pressure tests, respectively. Note that an intensity of radiant heat higher than that used in ligated animals was applied in the study on acute thermal nociception. Gabapentin (30 and 100 mg kg⁻¹, i.p. in (a) and 100 μg, i.c.v. in (b)) was administered at time zero. Each point represents the mean±s.e.m. of six or seven separate experiments. Ordinates: mean PWLs (plantar test; left) and nociceptive threshold (paw pressure; right). Abscissae: time in minutes after gabapentin injection.