qRT-PCR was conducted as described previously.18 (link) The whole brain or PAs were homogenized and mixed with Trizol reagent for RNA extraction. The yields of RNA were assessed using a Nanodrop 2000 spectrophotometer. cDNA synthesis was conducted using a cDNA Synthesis Supermix (TAKARA, Japan). qRT-PCR assays were performed using the SYBR qPCR Supermix Plus (TAKARA, Japan). β-actin was used to normalize gene expression data. To detect miRNA expression, total RNA was reverse transcribed and then mixed with TaqMan Universal PCR Master Mix (TAKARA, Japan) and miRNA-specific TaqMan primers (Springen, Nanjing, China). MiRNA expression data were normalized to U6 RNA. The fold-change of gene expression was measured using the 2−ΔΔCt method.18 (link) All primer sequences for qRT-PCR are presented in Supplementary Table S1.