Fig. 3.

Effect of acute (panel A) and subchronic (panel B) treatment with sildenafil in the forced swim test in mice subjected to the acute restraint stress. In acute studies, sildenafil was administered i.p. 30 min before the test. In subchronic studies, sildenafil was administered once daily for 14 consecutive days. Control animals received 1 % Tween 80 + 1 % DMSO. Each experimental group consisted of 10–12 animals. Data are presented as means + SEM. * p < 0.05, ** p < 0.01, *** p < 0.001 as compared to the control group; ^### p < 0.001 as compared to the stressed control group (one-way ANOVA followed by Tukey post hoc test)