NPY1R and major depressive disorder: The decrease of NPYY1 agonist binding induced by galanin and the demonstrated cross-inhibition of c-Fos expression in the dorsal raphe upon GalR and NPYY1 agonist co-activation provides one possible basis for the use of synergistic interactions of GalR subtype specific antagonists and NPYY1 receptor agonists as a strategy for treatment of depression.