Acute administration of the CB1 cannabinoid receptor antagonist SR 141716A induces anxiety-like responses in the rat.
Animal models have revealed that psychoactive cannabinoids induce both anxiolytic and anxiety-like reactions which are dose- and context-dependent. In the present study we examined the acute actions of the CB1 cannabinoid receptor antagonist SR 141716A in both the defensive withdrawal test and the elevated plus-maze in rats. Acute administration of SR 141716A (0.1, 1 and 3 mg kg-1) induced defensive responses in both anxiety tests, at a dose of 3 mg kg-1. This dose had no effect on horizontal locomotor activity and did not activate the hypothalamus-pituitary-adrenal axis, although several cannabinoid withdrawal-like behavioural symptoms were observed. These results demonstrate that blockade of the endogenous cannabinoid tone might induce anxiety-like responses in rats.
Navarro
M
M
Departamento de Psicobiología, Facultad de Psicología Instituto Complutense de Drogodependencias, Universidad Complutense, Madrid, Spain.
Hernández
E
E
Muñoz
R M
RM
del Arco
I
I
Villanúa
M A
MA
Carrera
M R
MR
Rodríguez de Fonseca
F
F
D000818:Animals; D001007:Anxiety / Q000139:chemically induced*; D001522:Behavior, Animal / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D008297:Male; D010880:Piperidines / Q000008:administration & dosage / Q000494:pharmacology*; D011720:Pyrazoles / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D043882:Receptors, Cannabinoid; D011955:Receptors, Drug / Q000037:antagonists & inhibitors*; D000077285:Rimonabant; D013997:Time Factors
D010880:Piperidines; D011720:Pyrazoles; D043882:Receptors, Cannabinoid; D011955:Receptors, Drug; D000077285:Rimonabant