Agmatine and imidazoline receptors: their role in opioid analgesia, tolerance and dependence

Cell Mol Neurobiol. 2008 Aug;28(5):629-41. doi: 10.1007/s10571-007-9164-y. Epub 2007 Jul 25.


Agmatine is an endogenous amine that is synthesized following the decarboxylation of L-arginine by arginine decarboxylase. Agmatine exists in mammalian brain and has been proposed as a neurotransmitter and/or neurotransmodulator. Agmatine binds to several targets and is considered as an endogenous ligand for imidazoline receptors. This review, mainly based on our research work in the past decade, focused on the modulations by agmatine action on imidazoline receptors to opioid analgesia, tolerance and dependence, and its possible neurochemical mechanisms. We went on to propose that agmatine and imidazoline receptors constitute a novel system of modulating opioid functions.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Agmatine / metabolism*
  • Agmatine / pharmacology
  • Agmatine / therapeutic use
  • Analgesics, Opioid / pharmacology*
  • Animals
  • Brain / drug effects
  • Brain / metabolism
  • Brain Chemistry / physiology
  • Drug Tolerance*
  • Humans
  • Imidazoline Receptors / metabolism*
  • Opioid-Related Disorders / drug therapy
  • Opioid-Related Disorders / metabolism*
  • Opioid-Related Disorders / physiopathology
  • Synaptic Transmission / drug effects
  • Synaptic Transmission / physiology


  • Analgesics, Opioid
  • Imidazoline Receptors
  • Agmatine