2.4. Intracerebroventricular Injection in the Left Lateral Ventricle (LV)

Unilateral microinjections of drugs were made using the stellar rat stereotaxic frame (Stoelting Co., Wood Dale, IL, USA). A craniotomy in the left LV was performed with a trephination bur of 1/32 inches to expose the surface of the skull. A glass micropipette (tip diameter 40–50 µm) was inserted using the bregma coordinates: AP = −1.3 mm, L = −1.8 mm, V = 3.6 mm [43]. Drugs were injected through a microinfusion pump (BASI Syringe Pump, MD-1000, West Lafayette, IN, USA) at a rate of 5 µL/min for 2 min, with a connected syringe of a polyethylene tube to the injection cannula. Finally, the cannula was removed, and the craniotomy was sealed with bone wax (Ethicon, Livingstone, UK).