Table 1.

Experimental protocols and the respective doses used.

Drugs	Dose	References
Haloperidol—nonselective dopaminergic receptor antagonist	0.2 mg/kg (i.p.)	[25,38]
Sulpiride—selective dopamine D2 receptor antagonist	50 mg/kg (i.p.)	[25,38]
Propranolol—β-adrenoceptor antagonist	2 mg/kg (i.p.)	[48]
Caffeine—nonselective adenosine receptor antagonist	3 mg/kg (i.p.)	[47]
AM281—selective CB1 receptor antagonist / inverse agonist	1 mg/kg (i.p.)	[49]
AM630—selective inverse agonist for the CB2 receptor	1 mg/kg (i.p.)	[49]