The antinociceptive effects of JWH-015 in chronic inflammatory pain are produced by nitric oxide-cGMP-PKG-KATP pathway activation mediated by opioids
Negrete, Roger (Institut d'Investigació Biomèdica Sant Pau)
Hervera Abad, Arnau (Institut d'Investigació Biomèdica Sant Pau)
Leánez, Sergi (Institut d'Investigació Biomèdica Sant Pau)
Martín-Campos, Jesús M. (Institut d'Investigació Biomèdica Sant Pau)
Pol, Olga (Institut d'Investigació Biomèdica Sant Pau)
Universitat Autònoma de Barcelona

Date:	2011
Abstract:	Background: Cannabinoid 2 receptor (CB2R) agonists attenuate inflammatory pain but the precise mechanism implicated in these effects is not completely elucidated. We investigated if the peripheral nitric oxide-cGMP-protein kinase G (PKG)-ATP-sensitive K+ (KATP) channels signaling pathway triggered by the neuronal nitric oxide synthase (NOS1) and modulated by opioids, participates in the local antinociceptive effects produced by a CB2R agonist (JWH-015) during chronic inflammatory pain. Methodology/Principal Findings: In wild type (WT) and NOS1 knockout (NOS1-KO) mice, at 10 days after the subplantar administration of complete Freund's adjuvant (CFA), we evaluated the antiallodynic (von Frey filaments) and antihyperalgesic (plantar test) effects produced by the subplantar administration of JWH-015 and the reversion of their effects by the local co-administration with CB2R (AM630), peripheral opioid receptor (naloxone methiodide, NX-ME) or CB1R (AM251) antagonists. Expression of CB2R and NOS1 as well as the antinociceptive effects produced by a high dose of JWH-015 combined with different doses of selective L-guanylate cyclase (ODQ) or PKG (Rp-8-pCPT-cGMPs) inhibitors or a KATP channel blocker (glibenclamide), were also assessed. Results show that the local administration of JWH-015 dose-dependently inhibited the mechanical and thermal hypersensitivity induced by CFA which effects were completely reversed by the local co-administration of AM630 or NX-ME, but not AM251. Inflammatory pain increased the paw expression of CB2R and the dorsal root ganglia transcription of NOS1. Moreover, the antinociceptive effects of JWH-015 were absent in NOS1-KO mice and diminished by their co-administration with ODQ, Rp-8-pCPT-cGMPs or glibenclamide. Conclusions/Significance: These data indicate that the peripheral antinociceptive effects of JWH-015 during chronic inflammatory pain are mainly produced by the local activation of the nitric oxide-cGMP-PKG-KATP signaling pathway, triggered by NOS1 and mediated by endogenous opioids. These findings suggest that the activation of this pathway might be an interesting therapeutic target for the treatment of chronic inflammatory pain with cannabinoids.
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, fins i tot amb finalitats comercials, sempre i quan es reconegui l'autoria de l'obra original.
Language:	Anglès
Document:	Article ; Versió publicada
Subject:	Dolor crònic ; Chronic inflammatory pain
Published in:	PloS one, Vol. 6, Issue 10 (October 2011) , p. e26688, ISSN 1932-6203

DOI: 10.1371/journal.pone.0026688
PMID: 22031841

11 p, 547.9 KB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Health sciences and biosciences > Institut de Neurociències (INc)
Research literature > UAB research groups literature > Research Centres and Groups (research output) > Health sciences and biosciences > Institut de Recerca Sant Pau
Articles > Published articles