Golgi staining

The morphology of dendritic spines in the brain was analyzed using a FD Rapid GolgiStain Kit (FD Neurotechnologies, Elliot City, MD, USA) according to the manufacturer’s instructions. Briefly, after being anesthetized, the mouse brains were quickly removed and washed in double distilled water (DDW). Subsequently, the brains were submerged in impregnation solution for 2 weeks at room temperature in the dark. The impregnation solution was replaced on the next day. Samples were removed to solution C for 2 days at room temperature in the dark, sectioned into 200 μm sections by a cryostat microtome and placed onto microscope slides. Sections were washed three times for 10 min each and placed in a mixture composed of solution D, solution E and DDW for 10 min followed by two rinses in DDW for 4 min each. The slides were dehydrated, cleared and coverslipped.