Imipramine

For the induction of the experimental parkinsonism, stereotactic surgery was performed for microinjection of the neurotoxin 6-OHDA (Sigma-Aldrich, Saint Louis, MO, USA) into the right MFB [32 (link)]. For efficacy and selectivity of the lesion, the animals were treated with imipramine (Alpha Aesar, Tewksbury, MA, USA; 20 mg/kg; intraperitoneal), a noradrenaline and serotonin reuptake inhibitor, 30 min before 6-OHDA infusion, to prevent 6-OHDA from being taken up by noradrenergic terminals. Subsequently, the animals were anesthetized with ketamine (Dopalen, Sespo Indústria e Comércio Ltda, Paulínia, SP, Brazil; 70 mg/kg; intraperitoneal) and xylazine (Anasedan, Sespo Indústria e Comércio Ltda, Paulínia, SP, Brazil; 10 mg/kg; intraperitoneal) and fixed in a stereotaxic apparatus (Insight Equipamentos^®, Ribeirão Preto, SP, Brazil). After exposing the animal’s skull, the coordinates of the right MFB were taken for unilateral 6-OHDA microinjection (AP: −4.3 mm, ML: +1.6 mm, and DV: −8.3 mm, from bregma [31 ]. Subsequently, 4 µL (at a rate of 0.5 µL/min) of 6-OHDA were microinjected into 0.9% saline solution containing 0.1% ascorbic acid or vehicle only (sham-operated control animals). Finally, the incision was sutured, and the animal was placed in a heated box under a thermal blanket for recovery from anesthesia.

Clomipramine, imipramine, amitriptyline, maprotiline,
and mianserin were purchased from Alfa Aesar
(Lancashire, UK). Opipramol, protriptyline, nortriptyline,
desipramine, and cisplatin were obtained from
SigmaAldrich (Taufkirchen, Germany).