Fig. 4.

Effects of stress on the expression of tryptophan hydroxylase (TPH) 2 in the dorsal raphe nucleus (DRN) of modulator of apoptosis 1 (MOAP-1)^−/− (KO) and wild-type control (WT) mice (age 3–6 months). a Brightfield image of a coronal section of mouse midbrain at − 4.6 mm from Bregma (left panel). TPH2 immunofluorescent staining can be seen concentrated in the DRN. Scale bar = 200 μm (middle panel) and 100 μm (right panel). b Representative photomicrographs of TPH2 immunofluorescent staining in the DRN of the WT and MOAP-1^−/− mice with or without stress treatment. Scale bar = 200 μm. c Number of TPH2 immunopositive cells in the DRN in WT and MOAP-1^−/− mice with or without stress treatment, n = 3–6. Data are presented as mean ± SEM. ANOVA: F = 5.917, P < 0.05. *P < 0.05 for control vs stressed WT mice by Bonferroni correction. d 5-HT levels in midbrain of WT and MOAP-1^−/− mice with or without stress treatment, n = 4. Data are presented as mean ± SEM. ANOVA: F = 4.366, P < 0.05. *P < 0.05 for control vs stressed WT mice by Bonferroni correction