(5-Leucine)Enkephalin
PreclinicalModified endogenous opioid peptide
Research material. Not for human or animal consumption.
Research overview
Leucine-enkephalin, Tyr-Gly-Gly-Phe-Leu, is one of the two enkephalins discovered by Hughes and Kosterlitz in 1975, the first endogenous opioid peptides identified. It is cut from proenkephalin and prefers delta-opioid receptors, with weaker action at mu receptors. Its N-terminal Tyr-Gly-Gly-Phe sequence is the shared 'opioid message' found at the start of endorphins and dynorphins. Enzymes break it down within minutes, so it is used mainly as a receptor reference, analytical standard and starting point for stable analogues.
Laboratory, computational, ex vivo or animal model research is the main evidence base.
Questions about (5-Leucine)Enkephalin
PRODUCT QUESTIONSWhat is (5-Leucine)Enkephalin?
(5-Leucine)Enkephalin is the five residue peptide tyrosine, glycine, glycine, phenylalanine, leucine. It is an endogenous opioid peptide derived from proenkephalin and is the shortest member of its family.
What research has been published on (5-Leucine)Enkephalin?
Research covers opioid receptor binding and signalling, pain and stress biology, its rapid breakdown by aminopeptidase N and neprilysin, and design of modified analogues and prodrugs that resist those enzymes. It is also used as a calibration standard in mass spectrometry.
What batch documentation should accompany (5-Leucine)Enkephalin?
(5-Leucine)Enkephalin: Ask for the COA and analytical reports for the batch being quoted. Ask for mass spectrometry, HPLC purity that separates the methionine enkephalin analogue and the shortened tetrapeptide, and peptide content.
How should (5-Leucine)Enkephalin storage conditions be assessed?
Store leucine enkephalin dry at −20°C, protected from moisture. The powder is stable, but solutions should be kept cold and free of enzymes or microbes.