The diverse physiological effects of Galanin, a biologically active neuropeptide, are mediated through cell surface G protein-coupled receptors. To date, three galanin receptor subtypes, GALR1, GALR2 and GALR3, have been cloned. Galanin, widely distributed in the central and peripheral nervous systems and the endocrine systems, binds to galanin receptors to induce several regulatory
functions in neuronal cells, including neuroregeneration, control of endocrine and exocrine secretions, and modulation of sensory and behavioral functions. Galanin agonists have been shown to have therapeutic application in treatment of chronic pain; galanin antagonists have therapeutic potential in treatment of Alzheimer"s disease, depression, and feeding disorders.