Addiction-related effects of DOV 216,303 and cocaine: A comparative study in the mouse

DOV 216,303, an inhibitor of serotonin, noradrenaline and dopamine reuptake, belongs to a new line of drugs called 'triple reuptake inhibitors' that have been proposed for treatment of depression. The addictive drug cocaine has similar mechanism of action and exerts rewarding effects by blocking reuptake of dopamine, leading to increased extracellular concentrations of dopamine in the nucleus accumbens. Thus, DOV 216,303 and other triple reuptake inhibitors might be speculated to exhibit abuse potential, limiting their future therapeutic use. To further elucidate potential addictive properties of DOV 216,303, we conducted a comparative study of addiction-related effects of DOV 216,303 and cocaine in mice using acute self-administration, conditioned place preference (CPP) and drug-induced hyperlocomotion. Effects on accumbal extracellular dopamine levels were determined using microdialysis, and we measured monoamine receptor occupancy as well as brain and plasma exposure. DOV 216,303 was self-administered acutely in the same dose range as cocaine. However, in the CPP model, DOV 216,303 did not induce place preference at doses where cocaine caused place preference. Higher doses of DOV 216,303 than cocaine were needed to induce hyperlocomotion and increase extracellular accumbal dopamine with effective doses being higher than effective doses used in depression models. Moreover, DOV 216,303 displayed a pharmacokinetic profile with lower potential for addiction than cocaine. Thus, high levels of DAT occupancy were reached slower and decayed more slowly after DOV 216,303 than cocaine administration. The present study shows that acute administration of DOV 216,303 displays some addictive-like properties in mice, but these were less pronounced than cocaine, most likely due to different pharmacokinetic profiles.