Figure 2.

Functional competition between GUO and adenosine (ADO) or selective agonists for A₁R and A_2AR on GUO-mediated anxiolytic-like effect evaluated by EPM test during a 5 min session. Pretreatment with ADO (10 mg/kg or 30 mg/kg) resulted in a complete block of anxiolytic-like effect of GUO (30 mg/kg) with significant decrease in (A) number of open arm entries [F_(5,62) =6.972, p < 0.0001], (B) time spent in open arms [F_(5,62) = 6.566, p < 0.0001] and (C) the ratio of time in open arm and total time in arms [F_(5,62) = 18.33, p < 0.0001], when compared to GUO treated group. Pretreatment with A₁R agonist CPA (0.1 mg/kg) or with A_2AR agonist CGS (0.4 mg/kg) was able to completely block the anxiolytic-like effect of GUO (30 mg/kg) with significant decrease in (D) number of open arm entries [F_(5,60) = 5.450, p < 0.0005], (E) time spent in open arms [F_(5,60) = 22.29, p < 0.0001] and (F) the ratio of time in open arm and total time in arms [F_(5,60) = 15.54, p < 0.0001], when compared to GUO treated group. CGS alone produced a significant reduction in time spent in open arms and ratio of time in open arm and total time in arms as compared to control group (Ctrl): each bar represents the mean value ± SD. Tukey test: * p < 0.05, ** p < 0.01; *** p < 0.001. Ctrl raw mean values: (A) 6.23; (B) 76.23 s; (C) 0.33; (D) 7; (E) 97.88 s; (F) 0.43.