The central melanocortin system is defined anatomically as a collection of central nervous system circuits which include:
- Neurons that express hypothalamic neuropeptide Y and agouti gene-related protein or proopiomelanocortin (POMC) and that originate in the arcuate nucleus.
- Brainstem POMC neurons originating in the commissural nucleus of the solitary tract (cNTS).
- Downstream targets of these proopiomelanocortic and agouti related protein neurons expressing the melanocortin-3 and melanocortin-4 receptors