P118.-Activation of Cannabinoid CB1 Receptor within Nucleus Accumbens Core Underlies Restraint Stress-Induced Reinstatement in Extinguished Cocaine?Conditioned Animal
Andrea Susana Guzmán1°, Laura Noemí De Giovanni1°, Miriam Beatriz Virgolini1°, Liliana Marina Cancela1°
1°IFEC ? CONICET; Departamento de Farmacología. FCQ. UNC
andreasuguz@gmail.com
Endocannabinoid system, primarily through their actions at CB1 receptor, is implicated in drug relapse. Moreover, the Nucleus Accumbens (NAc), a high density cannabinoid CB1 receptors brain region, is involved in cocaine and stress-induced reinstatement. Previous results from our lab demonstrated that in extinguished cocaine-conditioned animals evaluated in a conditioned place preference test (CPP), the restraint-stress reinstated the cocaine CPP and that phenomenon depends on the glutamatergic transmission within NAc. Additionally, in our lab it has been revealed that intra-Core administration of AM251, a CB1 antagonist, abrogated that restraint stress-induced reinstatement. According to the previous protocol, extinguished cocaine-conditioned Wistar rats were microinjected intra-Core with a CB1 agonist, ACEA, (0, 0.001 or 0.01 fmol/side) or vehicle, and subsequently assigned to the following treatments: 1) Stressed Animals (SA): 15 min-restraint exposure, a non-reinstatement session, and 2) Control Animals (CA). Intra-core ACEA administration facilitated the restraint stress-induced reinstatement in SA. Our results support the hypothesis of the influence of CB1 receptors in restraint stress-induced reinstatement. Future studies will focus on a possible glutamate dependent mechanism within NAc Core to explain the effect of CB1 receptor activation on restraint stress-induced reinstatement.
