Modulation of stress- and cocaine prime-induced reinstatement of conditioned place preference after memory extinction through dopamine D3 receptor

Blockade of D3 receptor prevents changes in DAT and D3R expression in the mesolimbic dopaminergic circuit produced by social stress- and cocaine prime-induced reinstatement of cocaine-CPP

“…before being confined to the drug-paired compartment for 30 min and, after an interval of 4 h, received saline immediately before confinement in the vehicle-paired compartment for 30 min. The dose of 25 mg/kg of cocaine was selected on the basis of previous studies, which demonstrated that it induces a robust CPP (Guerrero-Bautista et al, 2019; Rodriguez-Arias et al, 2017). On days 3 and 5, animals received an injection of saline before being confined to the vehicle-paired compartment for 30 min and, after an interval of 4 h, received cocaine (25 mg/kg i.p.)…”

“…Animal acquired cocaine-CPP, as described previously (Guerrero-Bautista et al, 2019), followed by extinction training. From day 7 and during 7–8 weeks, depending on the group (which is approximately equivalent to 4 years in human (Quinn, 2005) animals underwent extinction sessions 2 days a week, which were conducted exactly as in the pre-test and the post-tests (free access to each compartment for 900 s).…”

“…and then tested to evaluate the reinstatement in the cocaine-induced CPP. The dose of cocaine prime, half of that used for conditioning, was chosen as it has been previously shown it elicits CPP reactivation in male mice that have undergone extinction of cocaine-induced CPP (Guerrero-Bautista et al, 2019; Maldonado et al, 2006; Rodriguez-Arias et al, 2009). The reinstatement (reinst) test was similar to the pre-C, post-C and ext-tests, that is, free entry to each chamber for 900 s. All procedures were performed in the colony room, a non-contingent place to the previous conditioning injections.…”

“…Control mice received a vehicle injection instead of the D3R antagonist. The conditioning and priming doses of cocaine were based on previously published studies in mice (Guerrero-Bautista et al, 2019; Rodriguez-Arias et al, 2009).…”

“…Accordingly, D3R has gained attention as a clinical target for treatment of addiction-related behavior (Ashby et al, 2015a; Ashok et al, 2017; Maramai et al, 2016; Sokoloff and Le Foll, 2017). Blockade of D3R has been shown to inhibit psychostimulant and opiate self-administration (Xi et al, 2005; You et al, 2019), conditioned place preference (CPP) to drugs of abuse (Xi et al, 2006), and reinstatement of drug-seeking behavior and CPP triggered by stress (Guerrero-Bautista et al, 2019; Xi et al, 2004).…”