2.9. Nissl staining of mouse brain tissue

Paraffin‐embedded mouse brain tissue sections were cut into slices. The slices were treated with xylene dewax (10 minutes x 3), absolute ethanol (2 minutes), 90% ethanol (2 minutes), 70% ethanol (2 minutes) and distilled water (2 minutes). The Nissl staining solution was added to the tissue and stained for 5 minutes. After washing twice with distilled water, the slices were dehydrated with 95% ethanol, treated in xylene for transparent for 5 minutes and sealed with neutral gum, followed by observation under the microscope.