Table 3.

Main findings supporting the involvement of CB2r in the regulation of the reinforcing and motivational effects of nicotine.

CB2r & Nicotine-Animal studies
Genetic manipulation CB2r
Genetic manipulation	Specie	Experimental paradigm	Results	References
CB2r deletion, knock-out (CB2-/-)	Swiss ICR mice	CPP	↓ Conditioned place preference	[49]
		ISA	↓ Motivation for nicotine consumption
		WS	↓ Withdrawal signs
CB2r deletion, knock-out (CB2-/-)	C57BL/6J mice	CPP	↓ Conditioned place preference	[82]
CB2r deletion in dopaminergic neurons, conditional knock-out (DAT-Cnr2-/-)	C57BL/6J mice	CPP	↓ Conditioned place preference	[86]
Pharmacological manipulation of CB2r
Doses	Specie	Experimental paradigm	Results	References
SR144528, CB2r agonist (3 mg/kg)	Wistar Rats	DT	No differences	[87]
WIN55,212-2, CB1r/CB2r agonist (1 mg/kg) + Rimonabant, CB1r agonist (1 mg/kg) or AM630, CB2r antagonist (5 mg/kg)	Long-Evans rats	ISA	↑ WIN55,212-2-induced nicotine relapse, blocked by rimonabant but not by AM630	[88]
AM1241, CB2r agonist (1–10 mg/kg)	Long-Evans rats	ISA	No differences	[89]
AM630, CB2r agonist (1.25–5 mg/kg)	Long-Evans rats	ISA	No differences
AM630, CB2r antagonist (1 mg/kg)	Swiss ICR mice	CPP	↓ Conditioned place preference	[49]
		ISA	↓ Motivation for nicotine consumption
		WA	↓ Withdrawal signs
SR144528, CB2r antagonist (3 mg/kg) O-1966, CB2r agonist (1–20 mg/kg)	C57BL/6J mice	CPP	↓ Conditioned place preference	[82]
	C57BL/6J mice	CPP	↑ Conditioned place preference

DT: Discrimination Task, ISA: Intravenous Self-Administration, WS: Withdrawal Syndrome, CPP: Conditioned Place Preference, ↑: increase, ↓: decrease.