Tynorphin is a synthetic

opioid peptide Opioid peptides are peptides that bind to opioid receptors in the brain; opiates and opioids mimic the effect of these peptides. Such peptides may be produced by the body itself, for example endorphins. The effects of these peptides vary, but t ...

which is a potent and

competitive Competition is a rivalry where two or more parties strive for a common goal which cannot be shared: where one's gain is the other's loss (an example of which is a zero-sum game). Competition can arise between entities such as organisms, indivi ...

inhibitor of the enkephalinase class of

enzyme Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products ...

s which break down the endogenous

enkephalin An enkephalin is a pentapeptide involved in regulating nociception in the body. The enkephalins are termed endogenous ligands, as they are internally derived and bind to the body's opioid receptors. Discovered in 1975, two forms of enkephali ...

peptide Peptides (, ) are short chains of amino acids linked by peptide bonds. Long chains of amino acids are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides. ...

s. It specifically inactivates dipeptidyl aminopeptidase III (DPP3) with very high efficacy, but also inhibits neutral endopeptidase (NEP), aminopeptidase N (APN), and angiotensin-converting enzyme (ACE) to a lesser extent. It has a pentapeptide structure with the

amino acid sequence Protein primary structure is the linear sequence of amino acids in a peptide or protein. By convention, the primary structure of a protein is reported starting from the amino-terminal (N) end to the carboxyl-terminal (C) end. Protein biosynthe ...

Val-Val-Tyr-Pro-Trp (VVYPW). Tynorphin was discovered in an attempt to develop an enkephalinase inhibitor of greater potency than spinorphin.

References

{{Opioidergics Tryptamines Opioids Pentapeptides Propionic acids Pyrrolidines

See also

References