Short communicationEvidence that the reward attenuating effect of the D1-like antagonist, SCH-23390, is not mediated by its agonist action at the 5-HT2c receptors

This study investigated the effect of the 5-HT2c receptor antagonist, SB-242,084, on the attenuation of brain stimulation reward by SCH-23390. An additional experiment determined the effectiveness of SB-242,084 at blocking the reward attenuating effect of 5-HT2c agonist, CP-809,101. Results show that SB-242,084 blocked the reward attenuating effect of CP-809,101 but failed to alter that of SCH-23390. These findings provide evidence that the agonist action of SCH-23390 at the 5-HT2c receptors does not contribute to its attenuating effect on reward.

Research highlights▶ The dopamine D1 receptor antagonist, SCH-23390, attenuates brain stimulation reward. ▶ SCH-23390 is also an agonist at the serotonin 2c receptor. ▶ Reward is attenuated by CP-809,101, a selective serotonin 2c receptor agonist. ▶ The serotonin 2c receptor antagonist, SB-242,084, prevents the attenuating effect of CP-809,101. ▶ SB-242,084 does not prevent the attenuating effect of SCH-23390.