Immunohistochemistry
The SNpc tissues from the other half of brain were fixed with 4% paraformaldehyde and sectioned at 20 µm using a freezing cryostat (Thermo Fisher, MA, USA). After 30 min reacting with 3% hydrogen peroxide to eliminate endogenous peroxidase, the slices were incubated with both mouse REV-ERB α antibody (1:100) and rabbit TH antibody (1:100) overnight. Alexa Fluor 594-conjugated goat anti-mouse IgG antibody (1:200, Cat# A11032, RRID:AB_2534091) and Alexa Fluor 488-conjugated goat anti-rabbit IgG antibody (1:200, Cat# A10008) were used for secondary antibody and Diamidino-2-phenylindole (Cat# C6628, Sigma-Aldrich, St. Louis, MO, USA) was used to stain cell nuclei. Representative images were captured using a confocal microscopy (Leica, Solms, Germany). All experimental procedures conformed withBritish Journal of Pharmacology guideline (Alexander et al., 2018).