Home > Catalog Peptides > Kyotorphins

If you find Creative Peptides is useful to satisfy your needs, please do not hesitate to contact us!


Browse products name by alphabetical order:

Cat. # Product Name Price
K05001 Neo-Kyotorphin Inquiry
K05002 Kyotorphin Inquiry
K05003 (D-Arg2)-Kyotorphin Inquiry


Kyotorphins, an endogenous dipeptide, are formed from tyrosine and arginine by a specific synthetase, and originally found in bovine and rat brain synaptosomes. It has a specific receptor coupled to Gi and phospholipase C and elicits enkephalin release. It takes part in the regulation of various adaptive reactions of the organism, so it plays a key role in pain modulation in the mammalian central nervous system (CNS). Kyotorphins have a neutral net charge at biological pH. The phenolic rings of kyotorphins interact with phospholipid molecules despite being exposed to the aqueous bulk medium.

Mechanism of action

Previous studies suggested that kyotorphin-induced opioid like analgesia may be mediated via a release of Met-enkephalin from the brain. It elicited a release of Met-enkephalin from brain slices but not of [3H]-GABA, [3H]-aspartate, endorphin and [3H]-noradrenaline. The neurochemical basis of mechanisms suggests that kyotorphins stimulates its specific receptor, followed by Gi and phospholipase C (PLC) activations. PLC mechanism leads to a Ca2+ influx in nerve ending particles or synaptosomes. Inositol 1, 4, 5-trisphosphate (InsP3) elicits Ca2+ transport through plasmalemmal InsP3 receptor but not through intra synaptosomal Ca2+ stores. kyotorphins -induced antinociceptive responses are mediated through its specific receptor. However, at extremely low doses (below femtomolar ranges) of nociceptin/orphanin the endogenous ligand of opioid receptor-like orphan receptor it is coupled to Gi, elicits nociceptive responses through its receptor and Gi. Potent peripheral nociceptive actions of kyotorphins occur through an InsP3-receptor-gated Ca2+ influx.

Application of kyotorphins

The abilities to discriminate rigid raft like membrane domains and the well-defined orientation in membranes showed that kyotorphins meets the structural constraints needed for receptor-ligand interaction, which represents a promising way for entrapment in a drug carrier and transport across the blood-brain barrier. According to the rate of post resuscitational restoration and survival after a 12-min heart arrest, the Kyotorphin can improve cardiovascular and neurological status, and accelerate restoration of vital functions within several days after resuscitation, so it has been used to improve cardiovascular and cerebral resuscitation after heart arrest.

1. Kastin, A. J., Honour, L. C., & Coy, D. H. (1981). Kyotorphins affect aversive pecking in chicks. Physiology & behavior, 27(6), 1073-1076.
2. Foppoli, C., Coccia, R., Blarzino, C., Cini, C., & Rosei, M. A. (1991). The peroxidase-catalyzed oxidation of kyotorphins. Biochemistry international, 23(1), 43-51.
3. Castanho, M., & Santos, N. (Eds.). (2011). Peptide drug discovery and development: translational research in academia and industry. John Wiley & Sons.

If you have any peptide synthesis requirement in mind, please do not hesitate to contact us at We will endeavor to provide highly satisfying products and services.

Useful Tools

Peptide Calculator

Abbreviation List

Peptide Glossary

Follow us on:

Copyright © 2008 - Creative Peptides. All rights reserved.


Address: 45-16 Ramsey Road, Shirley, NY 11967, USA

Tel: 1-631-624-4882

Fax: 1-631-614-7828



Tel: 44-207-097-1828