Serotonin7 Receptors (5-HT7Rs) and their Ligands

Abstract: Serotonin (5-HT) is involved in various physiological and pathological processes by interaction with 14 distinct receptor subtypes, grouped in seven classes of receptors (5-HT1-7) on the basis of amino acid sequence, pharmacology, and signal transduction pathways. The 5-HT7R is a G-protein coupled receptor with seven transmembrane domains. It was found by the application of molecular cloning and has been identified in rat, mouse, human, pig, and guinea pig. Although the biological functions of the 5-HT7Rs are poorly understood, preliminary evidence suggests that it may be involved in depression, control of circadian rhythms, and relaxation of vascular smooth muscles. For these reasons, the 5-HT7R has become a target for the development of novel drugs. This review will give a brief introduction of the pharmacology of 5-HT7R (molecular structure, distribution of 5- HT7R mRNA, localization of the 5-HT7R protein, functional correlates, and therapeutic potential) and a detailed survey of the 5-HT7R ligands, which have appeared in the literature in both papers and patents. Structureactivity relationships (SAR) of these ligands will also be described