CART peptide is a new neurotransmitter linked to reward and drug abuse, showing notable activity in the brain's dopamine systems.
In the nucleus accumbens, about 86% of CART peptide-containing neurons also have substance P, indicating a significant interaction, while CART and enkephalin do not co-exist in this area.
The colocalization of CART and substance P neurons follows a gradient, with more overlap in the front (rostral) parts of the nucleus accumbens, suggesting CART neurons may play an important role in the brain's reward pathways.