Table 2.
Main findings supporting the involvement of CB2r in the regulation of the reinforcing and motivational effects of cocaine.
| CB2r & Cocaine-Animals Studies | ||||
|---|---|---|---|---|
| Genetic Manipulation CB2r | ||||
| Genetic manipulation | Specie | Experimental paradigm | Results | References |
| Overexpression of the CB2r (CB2xP) | Swiss ICR mice | SM | ↓ Cocaine-induced motor sensitization | [48] |
| CPP | ↓ Conditioned place preference | |||
| ISA | ↓ Motivation for cocaine consumption | |||
| CB2r deletion in dopaminergic neurons, conditional knock-out (DAT-Cnr2-/-) | C57BL/6J mice | MA | ↑ Cocaine-induced hyperactivity | [86] |
| MS | ↑ Cocaine-induced motor sensitization (10 mg/kg) | |||
| CPP | ↓ Cocaine-induced motor sensitization (20 mg/kg) ↑ Conditioned place preference |
|||
| Pharmacological manipulation of CB2r | ||||
| Doses | Specie | Experimental paradigm | Results | References |
| JWH133, CB2r antagonist (10 and 20 mg/kg) | C57BL/6J mice | ISA | ↓ Motivation for cocaine consumption | [60] |
| MA | ↓ Cocaine-induced locomotor effect | |||
| GW405833, CB2r agonist (3 and 10 mg/kg) | C57BL/6J mice | ISA | ↓ Motivation for cocaine consumption | [81] |
| SR144528, CB2r antagonist (0.1, 0.3 and 1 mg/kg) |
Wistar rats | ISA | No differences in motivation for cocaine consumption ↓ Cocaine-triggered relapse (not conditioned stimulus-triggered relapse) |
|
| O-1966, CB2r antagonist (1, 3, 5, 10 and 20 mg/kg) | C57BL/6J mice | CPP | ↓ Conditioned place preference | [82] |
| JWH133, CB2r agonist (10 and 20 mg/kg) | C57BL/6J mice | ISA | ↓ Motivation for cocaine consumption | [83] |
| Long-Evans rats | ISA | ↑ Motivation for cocaine consumption | ||
| JWH133, CB2r agonist (3 mg/kg) | C57BL/6J mice | CPP | ↓ Conditioned place preference | [86] |
↑: increase,↓: decrease, MS: Motor Sensitization, CPP: Conditioned Place Preference, ISA: Intravenous Self-Administration, MA: Motor Activity.