*2.11. Fluoro-Jade B Staining*

The Fluoro-Jade B staining was done as described previously [28], and according to the instructions provided (Burlington, MA, USA, Cat #AG310, Lot #2159662). The slides were dried at room temperature for 24 h. Furthermore, the slides were dipped in a solution of 1% sodium hydroxide and 80% ethanol, for five min. After that, the slides were kept in 70% ethanol for 2 min and in D-water for 2 min, transferred into a potassium permanganate solution (0.06%) for 10 min, rinsed with D-water, and kept in 0.1% acetic acid solution and 0.01% Fluoro-Jade B solution for 20 min, washed with D-water, and dried for 10 min. The sections were covered using a DPX mounting medium, and the images were taken using a confocal laser microscope (FV 1000, Olympus, Tokyo, Japan). Integrated density was used for the quantification of the staining intensity and for the amount in the immunofluorescent microscopic image. ImageJ software (wsr@nih.gov, https://imagej.nih.gov/ij/) was used to quantify the integrated density, which represents the sum of the pixel values in an image.
