Endomorphin-1
Overview
Endomorphin-1 is a tetrapeptide (Tyr-Pro-Trp-Phe) that exhibits highly selective agonist activity at the mu-opioid receptor, the primary target for analgesic opioids. It is one of two endomorphin isoforms and represents the most selective endogenous mu-opioid ligand identified to date. Endomorphin-1 is distributed in pain-processing regions of the central nervous system. Its selective mu receptor activity theoretically offers potent analgesia with a potentially different side effect profile compared to less selective opioids.
Key Research Findings
Preclinical studies have shown that endomorphin-1 produces potent analgesia in rodent models when administered intrathecally or intracerebroventricularly. Challenges including poor metabolic stability, limited blood-brain barrier penetration, and rapid enzymatic degradation have prevented clinical development. Research efforts have focused on designing stabilized analogs and prodrug strategies to improve pharmacokinetic properties.
Endogenous peptide
Research Phase
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