, Volume 20, Issue 3, pp 161–166 | Cite as

Endomorphins as Agents for the Treatment of Chronic Inflammatory Disease

  • David S. Jessop
Novel Therapeutic Strategies


Endomorphin (EM)-1 and EM-2 are tetrapeptides located within the mammalian central nervous system and immune tissues, with high affinity and specificity for μ-opioid receptors. Most of the literature has focused on the analgesic properties of EM-1 and EM-2 in animal models of neuropathic or neurogenic pain, but there is persuasive evidence emerging that EMs can also exert potent anti-inflammatory effects in both acute and chronic peripheral inflammation. The purpose of this review is to present and evaluate the evidence for anti-inflammatory properties of EM-1 and EM-2 with a view to their potential for use in chronic human inflammatory disease. Distribution of EMs within the immune system and functional roles as immunomodulatory agents are summarized and discussed. Possible milestones to be met revolve around issues of peptide stability, biodegradability problems and optimal route and method of delivery. The potential for delivery of a low-cost drug with both peripheral anti-inflammatory and analgesic properties, effective in low doses, and targeted to the site of inflammation, should focus our attention on further development of EMs as potent therapeutic agents in chronic inflammation.


Morphine Opioid Peptide Analgesic Property Intraplantar Injection Neurogenic Pain 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Special thanks are owed to Louise Richards for her skill in reversed-phase HPLC. The author is grateful to The Wellcome Trust for research funding for endomorphin and related projects.

The author declares no conflict of interest regarding the contents of this manuscript.


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Copyright information

© Adis Data Information BV 2006

Authors and Affiliations

  1. 1.Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology (LINE)University of Bristol, Dorothy Hodgkin BuildingBristolUK

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