[Met5]-Enkephalin

Product Name: [Met5]-Enkephalin - 25 mg

Sequence One Letter Code: YGGFM

Sequence Three Letter Code: H-Tyr-Gly-Gly-Phe-Met-OH

Cas No: 58569-55-4

Chemical Formula:C27H35N5O7S

Molecular Weight: 573.7

Purity: 95%

Form: Lyophilized

Storage Conditions: - 20 °C

Research Area: Neurological Disease Research

SMILES: CSCC[C@@H](C(=O)O)NC(=O)[C@H](CC1=CC=CC=C1)NC(=O)CNC(=O)CNC(=O)[C@H](CC2=CC=C(C=C2)O)N

IUPAC: (2S)-2-[[(2S)-2-[[2-[[2-[[(2S)-2-amino-3-(4-hydroxyphenyl)propanoyl]amino]acetyl]amino]acetyl]amino]-3-phenylpropanoyl]amino]-4-methylsulfanylbutanoic acid

INCHIKEY: YFGBQHOOROIVKG-FKBYEOEOSA-N

INCHI:

InChI=1S/C27H35N5O7S/c1-40-12-11-21(27(38)39)32-26(37)22(14-17-5-3-2-4-6-17)31-24(35)16-29-23(34)15-30-25(36)20(28)13-18-7-9-19(33)10-8-18/h2-10,20-22,33H,11-16,28H2,1H3,(H,29,34)(H,30,36)(H,31,35)(H,32,37)(H,38,39)/t20-,21-,22-/m0/s1

Source / Species: pig

Conjugation: Unconjugated

Code Nacres: NA.26

Application: [Met5]-Enkephalin is an endogenous opioid pentapeptide derived from the proenkephalin precursor and plays a central role in nociceptive modulation. Distinguished by a methionine residue at position five, it interacts primarily with opioid receptors in the central and peripheral nervous systems, influencing analgesic and neuromodulatory responses. This peptide is extensively used in neuroscience and pharmacology research to study opioid receptor signaling, pain pathways, and endogenous mechanisms regulating stress and neurochemical transmission.

Current Research: [Met⁵]-Enkephalin (Tyr–Gly–Gly–Phe–Met) is an endogenous opioid pentapeptide generated from the proenkephalin precursor through proteolytic processing. It is one of the principal enkephalin peptides in mammals and plays a central role in nociceptive modulation and neuromodulatory signaling within the central and peripheral nervous systems. Distinguished by a methionine residue at position five, [Met⁵]-Enkephalin differs from [Leu⁵]-Enkephalin only at the C-terminal amino acid, yet this substitution influences receptor binding characteristics and metabolic stability. The peptide interacts predominantly with δ-opioid receptors (DOR) and, to a lesser extent, μ-opioid receptors (MOR), both of which are Gi/o-coupled GPCRs. Biological and Pharmacological Context Enkephalins function as endogenous ligands in the opioid system, modulating: Pain perception Stress responsiveness Reward and reinforcement pathways Neuroendocrine regulation Upon receptor activation, [Met⁵]-Enkephalin initiates signaling cascades that include: Inhibition of adenylyl cyclase and reduced cAMP levels Activation of G protein–gated inwardly rectifying potassium (GIRK) channels Inhibition of voltage-gated calcium channels Modulation of MAPK/ERK pathways These effects collectively reduce neuronal excitability and neurotransmitter release, contributing to analgesic and inhibitory neuromodulatory outcomes. Functional Applications 1. Pain and Analgesia Research [Met⁵]-Enkephalin is widely used in experimental models of acute and chronic pain to investigate endogenous opioid contributions to nociceptive regulation. It serves as a reference agonist for δ-opioid receptor–mediated antinociceptive mechanisms. 2. Opioid Receptor Signaling Studies In vitro systems expressing MOR or DOR utilize [Met⁵]-Enkephalin to evaluate: Ligand binding affinity G protein activation β-arrestin recruitment Receptor desensitization and internalization It is particularly useful for comparing receptor subtype selectivity and signaling bias. 3. Stress and Neuroendocrine Regulation Endogenous enkephalins participate in stress adaptation and hypothalamic–pituitary axis modulation. The peptide supports mechanistic studies examining how opioid tone influences stress hormone release and behavioral responses. 4. Neurochemical Transmission and Synaptic Modulation [Met⁵]-Enkephalin modulates dopaminergic, GABAergic, and glutamatergic signaling in various brain regions. It is commonly applied in electrophysiological and neurochemical assays to assess synaptic inhibition and receptor-mediated neurotransmission. Experimental Considerations As a short peptide, [Met⁵]-Enkephalin is susceptible to rapid enzymatic degradation by peptidases such as enkephalinases. Inclusion of peptidase inhibitors may be necessary in certain assay systems to preserve activity. Concentration ranges should be optimized according to receptor expression levels and assay sensitivity.