*2.5. Biochemical Parameters Assay*

After the recording of behavioral data, zebrafish were euthanized (10 min immersion in ice water, 2–4 ◦C) until loss of opercular motions [28], and their brains were isolated for biochemical parameters assay. The brains were gently homogenized in ice 0.1 M potassium phosphate bu ffer (pH 7.4), 1.15% KCl with Potter Homogenizer (Cole-Parmer, Vernon Hills, IL, USA). The resulted homogenate was centrifuged at 960× *g* for 15 min. The supernatant was used for the estimation of acetylcholinesterase (AChE), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) specific activities, and malondialdehyde (MDA) level following the methods described in detail by Dumitru et al. [29]. Estimation of protein content was done through a bicinchoninic acid (BCA) protein assay kit (Sigma-Aldrich, Darmstadt, Germany) [30].
