Neuropeptide Y Y2 receptors modulate trace fear conditioning and spatial memory in the dorsal hippocampus

Background Neuropeptide Y (NPY), a highly conserved 36 amino acid peptide is widely distributed in the central nervous system. Besides its functions in various metabolic processes NPY has attracted considerable attention in modulating emotional-affective behavior. NPY exerts a pronounced anxiolytic effect most likely mediated by Y1 receptors, whereas stimulation of predominantly pre-synaptic Y2 receptors results in increased anxiety. The role of NPY Y2 receptors in the processing of emotional learning, however, remains still elusive.