Nocistatin blocks nociceptin action in pain transmission by inhibiting nociceptin-induced hyperalgesia and allodynia. Nociceptin is the ligand of the opioid receptor-like receptor (OPRL1). It may act as a transmitter in the brain by modulating nociceptive and locomotor behavior. Nociceptin is also involved in neuronal differentiation and development. Nocistatin is a 30-aa peptide processed from the prepronociceptin precursor that is cleaved in 3 chains, nocistatin, nociceptin and orphanin FQ2.H-Glu-Gln-Lys-Gln-Leu-Gln-OH or H-EQKQLQ-OH