Effects of compound B and PNU-120596 on exploratory motility. The normal, uninjured rats were administered either (A) compound B (3–30 mg·kg−1, s.c., t =−30 min) or vehicle (0.9% NaCl/0.5% glucose), (B) PNU-120596 (3–30 mg·kg−1, i.p., t =−30 min) or vehicle (15% MCBD), (C) diclofenac (3–30 mg·kg−1, p.o. t =−60 min) or vehicle (10% HBCD), (D) morphine (1–6 mg·kg−1, s.c. t =−30 min) or vehicle (0.9% NaCl/0.5% glucose), where t = pre-administration time of drug or vehicle, prior to being individually placed in motility cages. Automated recording of activity was measured as distance travelled (m) enabling the time course to be expressed in 3 min bins for the 30 min duration of the test. Inset: total distance travelled represented as percentage of vehicle recorded from 0–30 min. All groups n= 7 rats. Data are presented as mean ± SEM. *P < 0.05, **P < 0.01, ***P < 0.001 versus corresponding vehicle group (one-way anova followed by Bonferonni's t-test).