E-PS males showed an increased sensitivity to acute SSRI treatment. A–C, In a tail suspension test, E-PS males spent more time immobile (A), displayed an increased number of immobility bouts (B), and showed a decreased latency to first bout of immobility (C) compared with control males (**p < 0.01). For E-PS males, a subthreshold dose of 2.5 mg/kg citalopram significantly reduced bouts of immobility (B) and latency to first bout of immobility (C; #
p < 0.05) compared with vehicle. Citalopram (10 mg/kg) significantly reduced time spent immobile and bouts of immobility for control and E-PS males (#
p < 0.05; ##
p < 0.01) compared with vehicle. C, Citalopram (10 mg/kg) also significantly increased latency to first bout of immobility for E-PS males (#
p < 0.05). Data are mean ± SEM. n = 8.