ORPHANIN FQ NOCICEPTIN - A ROLE IN PAIN AND ANALGESIA, BUT SO MUCH MORE/

The publication of the delta opioid receptor sequence led to the cloni ng of three homologous receptors: the mu and kappa opioid receptors, a nd a novel opioid-like orphan receptor. The orphan receptor's endogeno us ligand, a 17-amino-acid peptide that resembles dynorphin, was named 'orphanin FQ' and 'nociceptin' (OFQ/N1-17). The OFQ/N1-17 receptor is expressed widely in the nervous system, and it is becoming clear that the peptide is likely to participate in a broad range of physiologica l and behavioral functions. At the cellular level, OFQ/N1-17 has much in common with the classical opioids; however, functional studies are now revealing distinct actions of this peptide Identified only two yea rs ago, QFQ/N1-17 has already attracted a great deal of attention. The number and diversity of papers focused on OFQ/N1-17 at the recent mee ting of the Society for Neuroscience augur an exciting future for this new peptide.