Galanin is a 29aa C-terminally amidated (30 aa, non-amidated in humans), highly conserved but unique neuroendocrine peptide originally isolated from intestine. The first 14aa are fully conserved in almost all species. Galanin is found in the brain and the gut. It modulates a variety of physiological processed including cognition/memory, sensory/pain processing, neurotransmitter/hormone secretion, and feeding behavior. Several N-terminally elongated (-7-29 and -9-29) or truncated biologically active forms of galanin have also been isolated. Galanin antagonists are chimeric peptides generated by linking the amino terminal portion of galanin to substance P (galantide, M15), bradykinin (M35), the neurokinin antagonist spantide (C7) or an idealized alpha helical region (M40) Galanin mediated its biological effects by interacting with high affinity cell surface receptors. Pharmacological studies with several peptide antagonists and antagonists of galanin receptor suggest the existence of multiple receptor subtypes, and three galanin receptors (GAL-R1, GAL-R2, and GAL-R3) have been clone thus far. These receptors belong to the family of G-protein coupled receptor superfamily, characterized by seven transmembrane domains.