Fig. 5.

The effect of sulpiride (SLP) and SCH 23390 (SCH) on anxiolytic-like behaviours induced by mitragynine (MG) and apomorphine (APO) in rats. The animals received a pre-test injection of saline (1 ml/kg), SLP (0.5 mg/kg) or SCH (0.02 mg/kg) 15 min before MG (40 mg/kg) or APO (0.5 mg/kg) treatments. Control (5 ml/kg), SLP and SCH groups received saline (1 ml/kg) 15 min before treatments. The anxiolytic-like behaviour indices include changes in %OAE (a), %OAT (b) and the total arm entries (c). Each bar represents mean ± SEM. ***p < 0.001 when compared to control group; ⁺ p < 0.05 and ⁺⁺⁺ p < 0.001 when compared to MG group; ^## p < 0.01 and ^### p < 0.001 when compared to APO group