The Role of the Dopamine D₁ Receptor in the Behavioural and Reinforcing Properties of Cocaine and Methamphetamine

Abstract

The current study examined the role of the dopamine D1 receptor in the behavioural and reinforcing properties of cocaine and methamphetamine. Using a mutant rat model, we carried out detailed locomotor analysis, conditioned taste avoidance, and conditioned place preference experiments. Of particular interest to this study was whether the role of the D1 receptor is dissociable for cocaine and methamphetamine. These drugs are both classified as psychostimulants and exert their effects via the dopamine transporter. However, research has shown that the specific binding profiles of these drugs, as well as other mechanisms by which they work are different. Major findings indicate that the D1 receptor is more involved in the behavioural and reinforcing processes associated with methamphetamine than cocaine. This research also provides further insight into the D1 mutant rat model.