[Orn5]-URP

Product Name:[Orn5]-URP

CAS No:782485-03-4

Purity:95%

Molar Mass:1003.2

Chemical Formula:C48H62N10O10S2

Storage:Store at -20 degrees Celsius

Sequence:ACFWXYCV

Target:UT

Application:

[Orn5]-URP, or [Ornithine5]-Urotensin II-Related Peptide, is a synthetic analog of urotensin II, where the fifth amino acid (usually a lysine) is replaced by ornithine. This modification can alter its interaction with the urotensin receptor (UT), a G protein-coupled receptor involved in cardiovascular regulation. [Orn5]-URP is utilized in research to explore the urotensin II signaling pathway, which is implicated in various cardiovascular and metabolic diseases, including hypertension and heart failure. Its applications are prominent in cardiovascular pharmacology and receptor-binding studies.

Current Research:

[Orn⁵]-Urotensin II–Related Peptide ([Orn⁵]-URP) is a synthetic analog of Urotensin II–Related Peptide (URP), a cyclic neuropeptide that serves as an endogenous ligand for the urotensin II receptor (UT). This analog features the substitution of the fifth amino acid residue with ornithine, resulting in the sequence Ala-Cys-Phe-Trp-Orn-Tyr-Cys-Val. This modification aims to investigate the structure-activity relationships of URP and its interaction with UT receptors.

Structural Characteristics

URP is an octapeptide with a conserved cyclic structure formed by a disulfide bond between two cysteine residues, creating a hexapeptide ring essential for its biological activity. The substitution of lysine with ornithine at position five in [Orn⁵]-URP introduces a shorter side chain, potentially altering the peptide's conformation and receptor binding affinity.

Receptor Specificity and Binding Affinity

The UT receptor, a G protein-coupled receptor, mediates various physiological effects, including vasoconstriction and modulation of central nervous system functions. Modifying URP at specific residues, such as the fifth position, allows researchers to assess the importance of side-chain length and charge in receptor binding and activation. Studies have shown that alterations at this position can significantly impact the peptide's affinity and efficacy at the UT receptor.

Physiological Implications

URP and its analogs, including [Orn⁵]-URP, play roles in cardiovascular regulation, such as influencing blood pressure and heart rate. By examining the effects of [Orn⁵]-URP, researchers can gain insights into the structural determinants critical for UT receptor activation and the subsequent physiological responses.

Research Applications

The development of [Orn⁵]-URP serves several research purposes:

Structure-Activity Relationship Studies: By analyzing how the ornithine substitution affects receptor binding and activation, scientists can better understand the structural features necessary for URP's biological activity.

Therapeutic Development: Insights gained from [Orn⁵]-URP studies can inform the design of novel UT receptor agonists or antagonists, potentially leading to new treatments for cardiovascular diseases or central nervous system disorders.

Conclusion

[Orn⁵]-URP is a valuable tool in the exploration of urotensin II receptor pharmacology. Its structural modification provides a means to dissect the molecular interactions between URP and its receptor, advancing our understanding of their roles in human physiology and aiding in the development of targeted therapeutic agents.

Reference:

Diallo, M., Jarry, M., Desrues, L., Castel, H., Chatenet, D., Leprince, J., ... & Gandolfo, P. (2008). [Orn5] URP acts as a pure antagonist of urotensinergic receptors in rat cortical astrocytes. Peptides, 29(5), 813-819.