[Dmt(1) ]N/OFQ(1-13)-NH(2) , a potent nociceptin/orphanin FQ and opioid receptor universal agonist.

Department of Experimental and Clinical Medicine, Section of Pharmacology and Neuroscience Center and National Institute of Neuroscience, University of Ferrara, Ferrara, Italy, Department of Pharmaceutical Sciences and LTTA, University of Ferrara, Ferrara, Italy, Department of Pharmacology, Istituto Superiore di Sanita, Rome, Italy, Department of Cardiovascular Sciences, Division of Anaesthesia, Critical Care and Pain Management, University of Leicester, Leicester Royal Infirmary, Leicester, UK, and Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI, USA Correspondence Girolamo Calo’, Department of Experimental and Clinical Medicine, Section of Pharmacology, University of Ferrara, via Fossato di Mortara, 19, 44100 Ferrara, Italy. E-mail: g.calo@unife.it