Sciatica Research Today is a free monthly online journal that collates and summarizes the latest research about Sciatica, including details on treatment, prevention, medication.

Delta-opioid receptors are critical for tricyclic antidepressant treatment of neuropathic allodynia.

Benbouzid M, Gavériaux-Ruff C, Yalcin I, Waltisperger E, Tessier LH, Muller A, Kieffer BL, Freund-Mercier MJ, Barrot M

Institut des Neurosciences Cellulaires et Intégratives, Centre National de Recherche Scientifique/Université Louis Pasteur, Strasbourg, France.

BACKGROUND: The therapeutic effect of antidepressant drugs against depression usually necessitates a chronic treatment. A large body of clinical evidence indicates that antidepressant drugs can also be highly effective against chronic neuropathic pain. However, the mechanism by which these drugs alleviate pain is still unclear. METHODS: We used a murine model of neuropathic pain induced by sciatic nerve constriction to study the antiallodynic properties of a chronic treatment with the tricyclic antidepressants nortriptyline and amitriptyline. Using knockout and pharmacological approaches in mice, we determined the influence of delta-opioid receptors in the therapeutic action of chronic antidepressant treatment. RESULTS: In our model, a chronic treatment by tricyclic antidepressant drugs totally suppresses the mechanical allodynia in neuropathic C57Bl/6J mice. This therapeutic effect can be acutely reversed by an injection of the delta-opioid receptor antagonist naltrindole. Moreover, the antiallodynic property of antidepressant treatment is absent in mice deficient for the delta-opioid receptor gene. CONCLUSIONS: The antiallodynic effect of chronic antidepressant treatment is mediated by a recruitment of the endogenous opioid system acting through delta-opioid receptors.

Published 25 February 2008 in Biol Psychiatry, 63(6): 633-6.
Full-text of this article is available online (may require subscription).

© 2004-2008 Sciatica Research Today. All Rights Reserved.