Crucial role of CB(2) cannabinoid receptor in the regulation of central immune responses during neuropathic pain

Neuropathic pain is a clinical manifestation of nerve injury difficult to treat even with potent analgesic compounds. Here, we used different lines of genetically modified mice to clarify the role played by CB2 cannabinoid receptors in the regulation of the central immune responses leading to the de...

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Detalles Bibliográficos
Autores: Racz, Ildiko, Nadal i Roura, Xavier, 1980-, Alferink, Judith, Baños i Díez, Josep Eladi, Rehnelt, Jennifer, Martín Sánchez, Miquel, 1971-, Pintado, Belén, Gutierrez-Adan, Alfonso, Sanguino, Elena, Manzanares, Jorge, Zimmer, Andreas, Maldonado, Rafael, 1961-
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2008
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:10230/16658
Acceso en línea:http://hdl.handle.net/10230/16658
http://dx.doi.org/10.1523/JNEUROSCI.3400-08.2008
Access Level:acceso abierto
Palabra clave:Cannabinoides -- Efectes fisiològics
Cannabinoides -- Receptors
Dolor -- Tractament
CB2 cannabinoid receptor
Microglia
Astrocytes
Neuropathic pain
Bone marrow chimera
Neuroinflammation
Descripción
Sumario:Neuropathic pain is a clinical manifestation of nerve injury difficult to treat even with potent analgesic compounds. Here, we used different lines of genetically modified mice to clarify the role played by CB2 cannabinoid receptors in the regulation of the central immune responses leading to the development of neuropathic pain. CB2 knock-out mice and wild-type littermates were exposed to sciatic nerve injury, and both genotypes developed a similar hyperalgesia and allodynia in the ipsilateral paw. Most strikingly, knock-outs also developed a contralateral mirror image pain, associated with an enhanced microglial and astrocytic expression in the contralateral spinal horn. In agreement, hyperalgesia, allodynia, and microglial and astrocytic activation induced by sciatic nerve injury were attenuated in transgenic mice overexpressing CB2 receptors. These results demonstrate the crucial role of CB2 cannabinoid receptor in modulating glial activation in response to nerve injury. The enhanced manifestations of neuropathic pain were replicated in irradiated wild-type mice reconstituted with bone marrow cells from CB2 knock-outs, thus demonstrating the implication of the CB2 receptor expressed in hematopoietic cells in the development of neuropathic pain at the spinal cord.