Effects of fluoxetine (10 mg/kg, b.i.d.) on behavioral responsivity to swim stress (A–F). Short-term (n = 5–6/group): FLX-treated rats displayed significantly longer latencies to immobility (A), lower total immobility (B), higher swimming and climbing counts and lower floating counts (C) when compared with VEH-treated control rats. Long-term (n = 15/group): FLX-treated rats displayed similar behavioral profile (D–F) as those tested in the short-term condition when compared with their VEH-treated control rats. *Significantly different from VEH-treated rats (p < .05). Data are presented as latencies to become immobile and total immobility (in seconds) and as cumulative 5-second intervals of swimming, climbing, and floating counts (mean ± SEM). b.i.d., twice daily; FLX, fluoxetine; FST, forced swim test; VEH, vehicle.