Efeito de diferentes ligantes do receptor canabinoide CB2 na hiperlocomoção induzida por cocaína ou quetamina

Abstract

Activation of the CB2 receptor inhibits the release of dopamine, representing a possible approach to the treatment of substance use disorders. This study aimed to test the hypothesis that a drug that activates or modulates the CB2 cannabinoid receptor inhibits hyperlocomotion induced by cocaine or ketamine. Male and female C57BL/6J mice were tested in the hyperlocomotion model induced by cocaine (15 mg/kg) or ketamine (30 mg/kg), treated with JWH-133 (0.3, 1 or 3 mg/kg) or -CF (25, 50 or 100 mg/kg) or EC21a (1, 3 or 10 mg/kg) i.p. 30 minutes before cocaine or ketamine administration. No CB2 receptor ligand reversed the hyperlocomotion effect induced by cocaine or ketamine in mice. Our study was the first to test the effects of JWH-133, -CF or EC21a on ketamine-induced hyperlocomotion and the first to test EC21a in the cocaine-induced hyperlocomotion protocol. The results do not necessarily refute the hypothesis that the CB2 receptor could be a therapeutic target for the treatment of substance use disorders. Further studies are needed to investigate the effects of different ligands of this receptor in chronic treatment protocols in different strains.