Wild-type (WT) C57BL/6 J male and female mice (Stock No. 000664) and Bdnfflox/flox (Stock No. 004339) mice were purchased from Jackson Laboratory (Bar Harbor, ME, USA). Bdnfflox/flox mice [55], which were generated by loxP sites flanking exon 9 of the Bdnf gene, were backcrossed to C57BL/6 J for at least 8–10 generations to generate a common genetic background. The PCR primers used for genotyping were as follows: Bdnf WT and flox, forward-5′-TGTGATTGTGTTTCTGGTGAC-3′, reverse-5′-GCCTTCATGCAACCGAAGTATG-3. All mice were housed in groups of five per cage under a 12-h light/dark cycle (lights on at 7:00 am) with ad libitum access to water and standard food pellets, except when explicitly stated differently for behavioral testing. For the experiments, both male and female mice aged between 7 and 15 weeks were used. This study was approved by the Institutional Animal Care and Use Committee of the Binzhou Medical University Hospital and was conducted in accordance with the National Institute of Health Guide for the Care and Use of Laboratory Animals (NIH Publications No. 80–23) revised 1996.
