FIGURE 4.

The acute antidepressant-like effects of S-ketamine were abolished by 5-HT depletion but rescued by the 5-HT_1B receptor agonist CP94253. In the FST, vehicle-pretreated FSL control rats displayed a significantly higher immobility (A) as well as lower swimming (B) and climbing (C) behavior compared to FRL controls. These behaviors were not affected by pCPA pretreatment. S-ketamine administration at 2 h before the FST decreased immobility and increased swimming in vehicle- but not pCPA-pretreated FSL rats. Supplementing this regimen with a 5-HT_1B receptor agonist 2 h prior to testing reduced immobility as well as increased swimming and climbing behavior relative to 5-HT depleted FSL control rats. Asterisks represent significant differences from vehicle-pretreated FSL control rats (^∗∗∗p < 0.001). Plus signs represent significant differences from pCPA-pretreated FSL control rats (⁺p < 0.05; ⁺⁺⁺p < 0.001). Values are mean ± SEM. The number of animals (n) is shown in each column. ˆ Data previously published in du Jardin et al. (2016).