Article

Involvement of 5-HT1A receptors in behavioural effects of the cannabinoid receptor agonist CP 55,940 in male rats.

Departamento de Fisiología Animal II, Facultad de Biología, Universidad Complutense, Madrid, Spain.
Behavioural Pharmacology (impact factor: 2.72). 03/2004; 15(1):21-7. pp.21-7
Source: PubMed

ABSTRACT We have studied the possible interaction between the cannabinoid receptor agonist CP 55,940 (1 and 50 microg/kg) and the 5-HT1A receptor antagonist WAY 100635 (1 mg/kg) in the modulation of plus-maze and holeboard activity in Wistar adult male rats. In the plus-maze, the higher dose of CP 55,940 induced an anxiogenic-like effect, whereas the lower dose induced anxiolytic-like responses. The 5-HT1A antagonist, which was silent in this test, attenuated the anxiogenic, but not the anxiolytic, effect of CP 55,940. In the holeboard, the higher dose of CP 55,940 significantly decreased head-dipping duration, and WAY 100635, which did not affect exploratory head-dipping when administered alone, antagonized this effect. The administration of WAY 100635 significantly increased grooming behaviour, and this effect was inhibited by the two doses of CP 55,940, which did not exert any effect, per se, on this parameter. We provide the first evidence implicating 5-HT1A receptors in anxiety-related behavioural responses to a cannabinoid agonist.

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Keywords

5-HT1A antagonist
 
5-HT1A receptor antagonist WAY 100635
 
anxiety-related behavioural responses
 
anxiolytic
 
cannabinoid agonist
 
cannabinoid receptor agonist CP 55,940
 
exploratory head-dipping
 
first evidence implicating 5-HT1A receptors
 
grooming behaviour
 
holeboard
 
holeboard activity
 
lower dose induced anxiolytic-like responses
 
modulation
 
possible interaction
 
Wistar adult male rats