Serotonergic and corticosteroid receptor expression are regulated differentially in response to stress in CRFR2-null mice. (A) mRNA expression of 5-HT1AR in the (B) dorsal raphe nucleus (DRN) and (C) median raphe nucleus (MRN); (D) tryptophan hydroxylase 2 (TPH2) mRNA in (E) DRN and (F) MRN; (G) serotonin transporter (SERT) protein expression in (H) hippocampal CA1, (I) CA2 and (J,K) subiculum (S); (L) glucocorticoid receptor (GR) mRNA expression in (M) CA1, (N) CA2 and (O,P) the paraventricular nucleus (PVN). Data presented as mean ± SEM for mRNA levels or densitometry signal (SERT). N = 6 to 8. ANOVA critical F(2,36) value = 3.259 for P ≤ 0.05, 5.248 for P ≤ 0.01, 8.420 for P ≤ 0.001. #P < 0.05, ##P < 0.01, ###P < 0.001 for effect of stress across genotypes. *P < 0.05, **P < 0.01, ***P < 0.001 ~P <0.10 in post-hoc analysis. ARS increased CRFR2 mRNA expression in whole brain of mice at all times points up to 48 h post-stress (Q), whereas CVMS decreased CRFR2 expression 7 days after the end of the CVMS protocol (R) . Data presented as mean ± SEM. N = 8. ANOVA critical F(5,42) value = 2.438 for P ≤ 0.05, 3.488 for P ≤ 0.01. *P < 0.05, ** P < 0.01 as compared with 0 hours in post-hoc analysis or with control group.