Antipsychotic profile of cannabidiol and rimonabant in an animal model of emotional context processing in schizophrenia.
OBJECTIVE
Clinical and neurobiological findings suggest that cannabinoids and their receptors are implicated in schizophrenia. Cannabidiol (CBD), a non-psychotomimetic compound of the Cannabis sativa plant, has been reported to have central therapeutic actions, such as antipsychotic and anxiolytic effects. We have recently reported that spontaneously hypertensive rats (SHR) present a deficit in contextual fear conditioning (CFC) that is specifically ameliorated by antipsychotics and aggravated by proschizophrenia manipulations. These results led us to suggest that the CFC deficit presented by SHR could be used as a model to study emotional processing impairment in schizophrenia. The aim of this study is to evaluate the effects of CBD and rimonabant (CB1 receptor antagonist) on the contextual fear conditioning in SHR and Wistar rats (WR).


METHODS
Rats were submitted to CFC task after treatment with different doses of CBD (experiment 1) and rimonabant (experiment 2).


RESULTS
In experiment 1, SHR showed a decreased freezing response when compared to WR that was attenuated by 1 mg/kg CBD. Moreover, all CBD-treated WR presented a decreased freezing response when compared to control rats. In experiment 2, SHR showed a decreased freezing response when compared to WR that was attenuated by 3 mg/kg rimonabant.


CONCLUSIONS
Our results suggest a potential therapeutical effect of CBD and rimonabant to treat the emotional processing impairment presented in schizophrenia. In addition, our results reinforce the anxiolytic profile of CBD.
Departamento de Farmacologia, Universidade Federal de Sao Paulo, Rua Pedro de Toledo, 669, Ed. de Pesquisas II, CEP 04039-032, Sao Paulo, SP, Brazil.
Raquel
R
Levin
Valeria
V
Almeida
Fernanda Fiel
FF
Peres
Mariana Bendlin
MB
Calzavara
Neide Derci
ND
da Silva
Mayra Akimi
MA
Suiama
Suzy Tamie
ST
Niigaki
Antonio Waldo
AW
Zuardi
Jaime Eduardo Cecilio
JE
Hallak
Jose Alexandre
JA
Crippa
Vanessa Costhek
VC
Abílio
D000818:Animals; D002185:Cannabidiol / Q000494:pharmacology* / Q000627:therapeutic use; D063387:Cannabinoid Receptor Antagonists / Q000494:pharmacology* / Q000627:therapeutic use; D004195:Disease Models, Animal; D004644:Emotions; D008297:Male; D010880:Piperidines / Q000494:pharmacology* / Q000627:therapeutic use; D011720:Pyrazoles / Q000494:pharmacology* / Q000627:therapeutic use; D017208:Rats, Wistar; D000077285:Rimonabant; D012559:Schizophrenia / Q000188:drug therapy*; D012565:Schizophrenic Psychology
D063387:Cannabinoid Receptor Antagonists; D010880:Piperidines; D011720:Pyrazoles; D002185:Cannabidiol; D000077285:Rimonabant