Changes in DA, serotonin (5-HT), norepinephrine (NE) and their metabolites in several brain regions of WT and CD157 KO mice after the FST, and effects of a single administration of selegiline. Data are shown for DA (A), ratio of DA metabolites to DA (B), 5-HT (C), 5-hydroxyindoleacetic acid (5-HIAA) (D), 5-HIAA/5-HT ratio (E) and NE (F) in μg/g wet tissue (mean ± SEM; n = 6−9). *P < 0.05, ***P < 0.005, saline-treated CD157 KO mice vs. saline-treated WT mice (Student’s t-test); &P < 0.05, &&P < 0.01, &&&P < 0.005, &&&&P < 0.001 vs. saline-treated WT mice (Dunnett’s test); #P < 0.05, ##P < 0.01, ###P < 0.005 vs. saline-treated CD157 KO mice (Dunnett’s test). (A) WT mice (striatum): F(3,30) = 14.106, P < 0.001; CD157 KO mice (striatum): F(3,29) = 5.833, P < 0.005; WT mice (hippocampus): F(3,30) = 5.315, P < 0.01; CD157 KO mice (hippocampus): F(3,29) = 6.113, P < 0.005; (B) WT mice (striatum): F(3,30) = 5.708, P < 0.005; CD157 KO mice (striatum): F(3,29) = 3.531, P < 0.05; (C)
CD157 KO mice (striatum): F(3,29) = 4.881, P < 0.01; (F) WT mice (cortex): F(3,30) = 3.358, P < 0.05; CD157 KO mice (cortex):F(3,29) = 4.415, P < 0.05. A two-way ANOVA showed no significant interaction between the effects of treatment and genotypes on monoamine content or their metabolites in brain regions examined [cortex: F(3,59) = 0.138, P = 0.937; striatum: F(3,59) = 0.372, P = 0.774; amygdala: F(3,56) = 1.127, P = 0.346; hippocampus: F(3,59) = 0.927, P = 0.434, (A); cortex: F(3,59) = 0.662, P = 0.579; striatum: F(3,59) = 0.832, P = 0.482; amygdala: F(3,56) = 0.226, P = 0.878; hippocampus: F(3,59) = 0.751, P = 0.526, (B); cortex: F(3,59) = 0.870, P = 0.462; striatum: F(3,59) = 0.901, P = 0.446; amygdala: F(3,56) = 0.028, P = 0.994; hippocampus: F(3,59) = 0.466, P = 0.707, (C); cortex: F(3,59) = 0.683, P = 0.556; striatum: F(3,59) = 0.308, P = 0.819; amygdala: F(3,56) = 0.441, P = 0.724; hippocampus: F(3,59) = 0.420, P = 0.739, (D); cortex: F(3,59) = 0.615, P = 0.608; striatum: F(3,59) = 0.055, P = 0.983; amygdala: F(3,56) = 0.157, P = 0.925; hippocampus: F(3,59) = 0.671, P = 0.573, (E); cortex: F(3,59) = 0.004, P = 1.000; striatum: F(3,59) = 0.069, P = 0.976; amygdala: F(3,56) = 0.010, P = 0.999; hippocampus: F(3,59) = 1.329, P = 0.274, (F)].