PACAP in the Defense of Energy Homeostasis.

The neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP) mediates diverse physiology from neuroprotection to thermoregulation. PACAP is well established as a master regulator of the stress response, regulating psychological and physiological equilibrium via the autonomic nervous system. Neuroanatomical and functional evidence support a role for PACAP in energy metabolism, including thermogenesis, activity, mobilization of energy stores, and appetite. Through integration of this evidence we suggest PACAP be included in the growing list of neuropeptides that mediate energy homeostasis. Future work to uncover the intricacies of PACAP expression and the molecular pathways responsible for PACAP signaling may show potential for this neuropeptide as a therapeutic target as well as further elucidate the complex neuroanatomical networks involved in defending energy balance.