After rehydrating the sections in PBS for 15 min at RT, endogenous peroxidases were quenched in 1/1000 phenylhydrazine (Sigma Aldrich) in PBS at 37 °C for 1 h. Sections were then washed 3 times in PBS for 10 min. The blocking of non-specific binding sites was performed by incubating the slides in 5% normal goat serum (Jackson Immunoresearch), 3% bovine serum albumin (Sigma Aldrich) and 0.1% Triton X-100 (Sigma Aldrich) in PBS for 2 h at RT. Primary antibodies were diluted at 1/1000 in blocking buffer and applied overnight at 4 °C. After 3 washes in PBS, a biotinylated goat anti-mouse (Vector Laboratories) secondary antibody diluted 1/200 in PBS was applied for 3 h at RT. The avidin/biotin Vectastain ABC Elite kit (Vector Laboratories) was used for peroxidase detection by Metal Enhanced DAB Substrate Kit (Thermo Fisher Scientific), according to manufacturer’s instructions. Slides were then washed in PBS and mounted in Eukitt mounting medium (Sigma Aldrich). Images of brain sections were taken on a Leica DM5500 microscope (Leica).