Citalopram hydrobromide

Yohimbine hydrochloride (Tocris, UK) was dissolved in distilled water. Citalopram hydrobromide (Tocris, UK), buspirone hydrochloride (Sigma, UK) amphetamine (Sigma, UK) and alpha-flupenthixol (Sigma, UK) were dissolved in 0.9 % saline. FG7142 (β-carboline-3-carboxylic acid N-methylamide) and diazepam (both Sigma, UK) were dissolved in 10 % dimethyl sulphoxide (DMSO; BDH Laboratory Supplies, UK), 20 % cremophor EL (Sigma, UK) and 70 % of 0.9 % saline. All drugs were administered at a final volume of 1 ml/kg.

Citalopram hydrobromide (Tocris), reboxetine mesylate (Tocris), paroxetine hydrochloride hemihydrate (Sigma), imipramine hydrochloride (Sigma), and methysergide (Sigma) were freshly dissolved into saline (NaCl 0.9%) before use. Compounds were dissolved in a final volume of 10mL/kg. α-FMHis (synthesized at Abbott Laboratories, Chicago, IL) was injected i.c.v. at the dose of 5 µg dissolved in 5 µL of saline. All doses were calculated as mg/kg of the free base. Control animals received saline. In reverse dialysis experiments, drugs were diluted in the perfusing Ringer’s solution. All other reagents and solvents were of high performance liquid chromatography (HPLC) grade or the highest grade available (Sigma).

Veratridine, dihydrokainic acid (DHK), 2,3-dioxo-6-nitro-1,2,3,4-tetrahydrobenzo[f]quinoxaline-7-sulfonamide disodium salt (NBQX), (S)-α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (s-AMPA) and citalopram hydrobromide were purchased from Tocris (Bristol, UK). 4-chloro-dl-phenylalanine methyl ester hydrochloride (pCPA) was purchased from Sigma-Aldrich (Tres Cantos, Spain).
For intracerebral microinfusion, Veratridine was dissolved in 12.5% dimethyl sulfoxide in artificial cerebrospinal fluid and pH adjusted to 6.5; DHK and s-AMPA were dissolved in PBS 10 × as previously reported;²⁹ NBQX and citalopram were dissolved in artificial cerebrospinal fluid. The microinfusion volume was 0.5 μl per side in all cases. pCPA was administered intraperitoneally, was daily prepared by dissolving in saline and pH was adjusted to 6.0 with 0.1 m NaOH.^{30 (link)}