The priming effect of food persists following blockade of dopamine receptors

• Published in: The European journal of neuroscience 2019-11, Vol.50 (9), p.3416-3427
• Main Authors: Evangelista, Czarina, Hantson, Arne, Shams, Waqqas M., Almey, Anne, Pileggi, Michael, Voisard, Jacques R., Boulos, Vanessa, Al‐qadri, Yaman, Gonzalez Cautela, Brunella V., Zhou, Fei Xiang, Duchemin, Jesse, Habrich, Andrew, Tito, Noemie, Koumrouyan, Ramela A., Patel, Smita, Lorenc, Victoria, Gagne, Collin, El Oufi, Khaoula, Shizgal, Peter, Brake, Wayne G.
• Format: Article
• Language: English
• Subjects: Dopamine; Dopamine D1 receptors; Dopamine D2 receptors; Dopamine receptors; Eticlopride; Food; incentive motivation; Motivation; natural reward; Operant conditioning; Reinforcement; Response time; SCH23390; Vigor
• ISSN: 0953-816X; 1460-9568
• DOI: 10.1111/ejn.14531

The priming effect of rewards is a boost in the vigor of reward seeking resulting from the previous receipt of a reward. Extensive work has been carried out on the priming effect of electrical brain stimulation, but much less research exists on the priming effect of natural rewards, such as food. While both reinforcement and motivation are linked with dopamine transmission in the brain, the priming effect of rewards does not appear to be dopamine‐dependent. In the present study, an operant method was developed to measure the priming effect of food and then applied to investigate whether it is affected by dopamine receptor antagonism. Long‐Evans rats were administered saline or one of the three doses (0.01, 0.05, 0.075 mg/kg) of the dopamine D1 receptor family antagonist, SCH23390, or the dopamine D2 receptor family antagonist, eticlopride. Although dopamine receptor antagonism affected pursuit of food, it did not eliminate the priming effect. These data suggest that despite the involvement of dopamine transmission in reinforcement and motivation, the priming effect of food does not depend on dopamine transmission. A taste of something rewarding can make you want more of it, and this is called the priming effect of rewards. Dopamine transmission is thought to mediate the wanting of rewards, but we show that the priming effect persists following dopamine receptor blockade. Understanding the mechanisms underlying the priming effect is important for consummatory disorders such as binge eating.