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Details

Stereochemistry ABSOLUTE
Molecular Formula C27H35N5O7S
Molecular Weight 573.661
Optical Activity UNSPECIFIED
Defined Stereocenters 3 / 3
E/Z Centers 0
Charge 0

SHOW SMILES / InChI
Structure of METENKEFALIN

SMILES

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

InChI

InChIKey=YFGBQHOOROIVKG-FKBYEOEOSA-N
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

HIDE SMILES / InChI

Molecular Formula C27H35N5O7S
Molecular Weight 573.661
Charge 0
Count
Stereochemistry ABSOLUTE
Additional Stereochemistry No
Defined Stereocenters 3 / 3
E/Z Centers 0
Optical Activity UNSPECIFIED

Metenkephalin (Met-enkephalin) is an endogenous opioid peptide that acts as an agonist at μ-opioid receptors (μORs) and δ-opioid receptors (δORs). Met-enkephalin exhibits neuromodulatory, antinociceptive/analgesic, antidepressant, and gastrointestinal motility modulating activities. Like other endogenous opioids, met-enkephalin modulates expression of opioid receptors and plays a role in reward/reinforcement signaling. Met-enkephalin is also involved in exercise-induced reversal of neuropathic pain and in animals undergoing the forced swim test, decreases immobility time. Met-enkephalin inhibits gastrointestinal muscle contractility, inhibiting motility and gastric emptying. Additionally, analogs of this peptide display anticancer and antiepileptic/anticonvulsant activities.

Approval Year

Doses

Doses

DosePopulationAdverse events​
250 ug/kg single, intravenous
MTD
Dose: 250 ug/kg
Route: intravenous
Route: single
Dose: 250 ug/kg
Sources:
unhealthy, ADULT
Health Status: unhealthy
Age Group: ADULT
Sex: M+F
Food Status: UNKNOWN
Sources:
DLT: Hypotension...
Dose limiting toxicities:
Hypotension (grade 3, 66.7%)
Sources:
50 ug/kg 2 times / day multiple, subcutaneous
Studied dose
Dose: 50 ug/kg, 2 times / day
Route: subcutaneous
Route: multiple
Dose: 50 ug/kg, 2 times / day
Sources:
unhealthy, ADULT
Health Status: unhealthy
Age Group: ADULT
Sex: M+F
Food Status: UNKNOWN
Sources:
AEs

AEs

AESignificanceDosePopulation
Hypotension grade 3, 66.7%
DLT
250 ug/kg single, intravenous
MTD
Dose: 250 ug/kg
Route: intravenous
Route: single
Dose: 250 ug/kg
Sources:
unhealthy, ADULT
Health Status: unhealthy
Age Group: ADULT
Sex: M+F
Food Status: UNKNOWN
Sources:
Sourcing

Sourcing

Vendor/AggregatorIDURL
PubMed

PubMed

TitleDatePubMed
Enhancement of the generation of cytotoxic T cells by endogenous opiates.
1986 Jul
Cloning and functional comparison of kappa and delta opioid receptors from mouse brain.
1993 Jul 15
Cloning and pharmacological characterization of a rat kappa opioid receptor.
1993 Nov 1
Pharmacological characterization of the cloned kappa-, delta-, and mu-opioid receptors.
1994 Feb
Patents

Patents

Sample Use Guides

All subjects treated with met-enkephalin 250 ug/kg iv weekly over 45 minutes
Route of Administration: Intravenous
In Vitro Use Guide
Curator's Comment: Isolated from human peripheral blood, neutrophils were incubated in the presence or absence of 10(-6) to 10(-10) M of Metenkephalin (M-ENK) and beta-END for 12 and 18 h. Apoptosis of neutrophils was determined in vitro by flow cytometric analysis of cellular DNA content and Annexin V-FITC protein binding to the cell surface.
Treatment with Metenkephalin (M-ENK) caused a significant increase in apoptotic cells after 18 h of culture: *0 M (control) versus 10(-10) M, p < or = 0.02; **10(-10) M versus 10(-10) M, p < or = 0.02.
Substance Class Chemical
Created
by admin
on Mon Mar 31 18:43:11 GMT 2025
Edited
by admin
on Mon Mar 31 18:43:11 GMT 2025
Record UNII
9JEZ9OD3AS
Record Status Validated (UNII)
Record Version
  • Download
Name Type Language
METENKEFALIN
INN  
INN  
Official Name English
SH-PENTAPEPTIDE-19
INCI  
INCI  
Preferred Name English
TYR-GLY-GLY-PHE-MET
Common Name English
OPIOID GROWTH FACTOR
Common Name English
MET-ENKEPHALIN
Common Name English
(MET5)-ENKEPHALIN
Common Name English
METHIONINE ENKEPHALIN
Common Name English
ENKEPHALIN-(5-L-METHIONINE)
Common Name English
NSC-374896
Code English
Metenkefalin [WHO-DD]
Common Name English
INNO-105
Code English
L-TYROSYLGLYCYLGLYCYL-L-PHENYLALANYL-L-METHIONINE .BETA.-ENDORPHIN HUMAN-(1-5)-PEPTIDE
Common Name English
metenkefalin [INN]
Common Name English
Classification Tree Code System Code
NCI_THESAURUS C308
Created by admin on Mon Mar 31 18:43:11 GMT 2025 , Edited by admin on Mon Mar 31 18:43:11 GMT 2025
FDA ORPHAN DRUG 388312
Created by admin on Mon Mar 31 18:43:11 GMT 2025 , Edited by admin on Mon Mar 31 18:43:11 GMT 2025
NCI_THESAURUS C67413
Created by admin on Mon Mar 31 18:43:11 GMT 2025 , Edited by admin on Mon Mar 31 18:43:11 GMT 2025
FDA ORPHAN DRUG 333011
Created by admin on Mon Mar 31 18:43:11 GMT 2025 , Edited by admin on Mon Mar 31 18:43:11 GMT 2025
NCI_THESAURUS C274
Created by admin on Mon Mar 31 18:43:11 GMT 2025 , Edited by admin on Mon Mar 31 18:43:11 GMT 2025
FDA ORPHAN DRUG 392213
Created by admin on Mon Mar 31 18:43:11 GMT 2025 , Edited by admin on Mon Mar 31 18:43:11 GMT 2025
Code System Code Type Description
WIKIPEDIA
Met-enkephalin
Created by admin on Mon Mar 31 18:43:11 GMT 2025 , Edited by admin on Mon Mar 31 18:43:11 GMT 2025
PRIMARY
FDA UNII
9JEZ9OD3AS
Created by admin on Mon Mar 31 18:43:11 GMT 2025 , Edited by admin on Mon Mar 31 18:43:11 GMT 2025
PRIMARY
RXCUI
1349278
Created by admin on Mon Mar 31 18:43:11 GMT 2025 , Edited by admin on Mon Mar 31 18:43:11 GMT 2025
PRIMARY RxNorm
ChEMBL
CHEMBL2108291
Created by admin on Mon Mar 31 18:43:11 GMT 2025 , Edited by admin on Mon Mar 31 18:43:11 GMT 2025
PRIMARY
DAILYMED
9JEZ9OD3AS
Created by admin on Mon Mar 31 18:43:11 GMT 2025 , Edited by admin on Mon Mar 31 18:43:11 GMT 2025
PRIMARY
DRUG BANK
DB12668
Created by admin on Mon Mar 31 18:43:11 GMT 2025 , Edited by admin on Mon Mar 31 18:43:11 GMT 2025
PRIMARY
ECHA (EC/EINECS)
261-335-8
Created by admin on Mon Mar 31 18:43:11 GMT 2025 , Edited by admin on Mon Mar 31 18:43:11 GMT 2025
PRIMARY
PUBCHEM
443363
Created by admin on Mon Mar 31 18:43:11 GMT 2025 , Edited by admin on Mon Mar 31 18:43:11 GMT 2025
PRIMARY
CAS
58569-55-4
Created by admin on Mon Mar 31 18:43:11 GMT 2025 , Edited by admin on Mon Mar 31 18:43:11 GMT 2025
PRIMARY
NCI_THESAURUS
C91011
Created by admin on Mon Mar 31 18:43:11 GMT 2025 , Edited by admin on Mon Mar 31 18:43:11 GMT 2025
PRIMARY
NSC
374896
Created by admin on Mon Mar 31 18:43:11 GMT 2025 , Edited by admin on Mon Mar 31 18:43:11 GMT 2025
PRIMARY
INN
8875
Created by admin on Mon Mar 31 18:43:11 GMT 2025 , Edited by admin on Mon Mar 31 18:43:11 GMT 2025
PRIMARY
SMS_ID
300000034342
Created by admin on Mon Mar 31 18:43:11 GMT 2025 , Edited by admin on Mon Mar 31 18:43:11 GMT 2025
PRIMARY
EPA CompTox
DTXSID90974125
Created by admin on Mon Mar 31 18:43:11 GMT 2025 , Edited by admin on Mon Mar 31 18:43:11 GMT 2025
PRIMARY
Related Record Type Details
TARGET -> AGONIST
TARGET -> AGONIST
TARGET -> AGONIST
SALT/SOLVATE -> PARENT
Related Record Type Details
ACTIVE MOIETY