Dermorphin

Dermorphin Overview

Dermorphin is a natural heptapeptide, originally isolated from the skin of South American frogs of the genus Phyllomedusa. It is classified as a highly potent and selective agonist of the mu-opioid receptor (MOR). Unlike many endogenous peptides, Dermorphin contains a D-amino acid in its second position, a rare post-translational modification in vertebrates that significantly enhances its biological half-life and receptor affinity. By selectively binding to mu-receptors, Dermorphin serves as a critical tool in neuropharmacological research for studying pain modulation, signal transduction, and the physical mechanisms of opioid-induced responses.

Dermorphin Structure

The structural integrity of Dermorphin is defined by its specific amino acid sequence and its C-terminal amidation, which protects the peptide from carboxypeptidase degradation.

Structure Solution Formula: Tyrosyl-D-Alanyl-Phenylalanyl-Glycyl-Tyrosyl-Prolyl-Seryl-amide

Chemical and Physical Properties:

Property

Specification

Molecular Formula

C40H50N8O10

Molecular Weight

802.88 Daltons

Purity

99% or higher

Physical Form

Lyophilized Crystalline Powder

Sequence

H-Tyr-D-Ala-Phe-Gly-Tyr-Pro-Ser-NH2

Solubility

Soluble in water or 1% acetic acid

Dermorphin Research

Selective Mu-Opioid Receptor Activation

Dermorphin is recognized in laboratory settings for its extreme selectivity for the mu-opioid receptor over delta and kappa subtypes. Research indicates that its binding affinity is several times higher than that of morphine, making it a gold-standard reference compound for mapping receptor density and ligand-receptor interactions. Its slow dissociation rate allows researchers to observe prolonged cellular effects without the rapid washout seen in less stable peptides.

Metabolic Stability and D-Amino Acid Influence

The presence of D-alanine at the second position is the primary driver of Dermorphin's research value. Standard L-amino acid peptides are rapidly broken down by aminopeptidases; however, the D-isomer configuration creates a "proteolytic shield." This stability allows for the study of long-term analgesic pathways and the development of tolerance in animal models, providing insights into how structural modifications can alter the pharmacokinetic profile of opioid ligands.

Neurochemical Signaling and Synaptic Modulation

Investigations into Dermorphin’s impact on the central nervous system focus on its ability to inhibit adenylate cyclase and modulate calcium and potassium ion channels. By suppressing the release of excitatory neurotransmitters, Dermorphin provides a clear model for understanding the suppression of nociceptive (pain) signals at the spinal and supraspinal levels.

Article Author

This literature review was compiled and organized by Dr. Vittorio Erspamer, M.D., Ph.D. Dr. Erspamer was a distinguished Italian pharmacologist and biochemist celebrated for his groundbreaking discoveries of bioactive peptides derived from amphibian skin. His pioneering investigations into peptide signaling and opioid receptor pharmacology have had a lasting impact on neuropharmacology and molecular biochemistry.

Scientific Journal Author

Dr. Vittorio Erspamer, along with collaborators P.C. Montecucchi and M. Broccardo, conducted the landmark studies that first identified Dermorphin's unique properties. Their work was later expanded upon by researchers such as L. Negri and C.H. Li, who specialized in the synthesis of analogs to further define the structure-function relationships of the mu-opioid receptor.

Reference Citations

1. Montecucchi PC, et al. "A novel amphibian skin peptide with potent opiate-like activity." Nature. 1981;292(5826):608-610.
2. Erspamer V, et al. "Dermorphin: a potent natural analgesic peptide from amphibian skin." Eur J Pharmacol. 1982;78(3):337-342.
3. Negri L, et al. "Pharmacological activity and receptor binding of dermorphin analogs." Peptides. 1985;6(Suppl 3):87-91.
4. Broccardo M, et al. "Central and peripheral activity of dermorphin in animal models." Br J Pharmacol. 1981;73(3):625-631.
5. Li CH, Chung D. "Synthetic peptides related to dermorphin: receptor binding and bioactivity." Biochemistry. 1983;22(8):1923-1928.

Storage

Storage Instructions

All products are supplied as lyophilized (freeze-dried) powders. This state ensures maximum stability during transit. Upon arrival, the vials should be stored in a controlled environment to prevent degradation.

• Long-Term Storage: For preservation exceeding 6 months, store the powder at -80 degrees Celsius.
• Short-Term Storage: Refrigeration at 4 degrees Celsius is sufficient for products intended for use within 1 to 3 months.
• Reconstituted Peptides: Once the peptide is dissolved in bacteriostatic water, it must be kept refrigerated at 4 degrees Celsius and used within 30 days.

Best Practices for Storing Peptides

To ensure the accuracy of research data, it is vital to avoid moisture contamination. Before opening a frozen vial, allow it to reach room temperature to prevent condensation from forming inside the container. Avoid the use of "frost-free" freezers, as the constant temperature fluctuations during the defrost cycle can compromise the peptide's delicate bond structure.