Dose-dependent induction of CPP or CPA by intra-pVTA ethanol: Role of mu opioid receptors and effects on NMDA receptors

Publication date: Available online 22 January 2020Source: Progress in Neuro-Psychopharmacology and Biological PsychiatryAuthor(s): Yolanda Campos-Jurado, Lucía Martí-Prats, Jose A. Morón, Ana Polache, Luis Granero, Lucía HipólitoAbstractThe neurobiological mechanisms underlying alcohol motivational properties are still not fully understood, however, the mu-opioid receptors (MORs) have been evidenced as central elements in the manifestation of the alcohol reinforcing properties. Drug-associated environmental stimuli can trigger alcohol relapse and promote alcohol consumption whereby N-methyl-d-aspartate (NMDA) receptors play a pivotal role. Here we sought to demonstrate, for the first time, that ethanol induces conditioned place preference or aversion (CPP or CPA) when administered locally into the ventral tegmental area (VTA) and the associated role of MORs. We further analyzed the changes in the expression and mRNA levels of GluN1 and GluN2A subunits in designated brain areas. The expression of CPP or CPA was characterized following intra-VTA ethanol administration and we showed that either reinforcing (CPP) or aversive (CPA) properties are dependent on the dose administered (ranging here from 35 to 300 nmol). Furthermore, the critical contribution of local MORs in the acquisition of CPP was revealed by a selective antagonist, namely β-Funaltrexamine. Finally, modifications of the expression of NMDA receptor subunits in the Nucleus Accumbens (NAc) and Hippocampus aft...
Source: Progress in Neuro Psychopharmacology and Biological Psychiatry - Category: Psychiatry Source Type: research