Met-Enkephalin
Overview
Met-enkephalin is a pentapeptide (Tyr-Gly-Gly-Phe-Met) that differs from leu-enkephalin only in its C-terminal amino acid. It acts as an endogenous opioid with preferential delta-opioid receptor activity and also binds mu-opioid receptors. Derived from proenkephalin, met-enkephalin is involved in pain modulation, stress responses, and immune regulation. Like other enkephalins, it is subject to rapid enzymatic degradation by aminopeptidases and enkephalinases.
Key Research Findings
Met-enkephalin has been characterized in numerous preclinical studies demonstrating analgesic and neuromodulatory effects when central degradation is prevented. Clinical translation has been hindered by the peptide's instability and inability to cross the blood-brain barrier. Synthetic analogs with enhanced stability, such as DADLE, have been investigated but have not achieved widespread clinical use.
Endogenous peptide
Research Phase
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