Cresyl violet (CV) stains the endoplasmic reticulum and the cellular nuclei in dark purple, which includes, in the brain, cell bodies of neurons and glial cells (Eilam-Altstädter et al., 2021) (link). The protocol followed guidelines of US Army Inst Pathol (Luna et al., 1968) , in which the sections were hydrated first, submerged for 1h15 in 0.01% Cresyl violet (Sigma Aldrich catalog #C5042) in a 0.1M acetate buffer (Anachemia, AC-8218) and 0.1M acetic acid (BDH 10001CU), and then dehydrated.