Nigrostriatal dopaminergic depletion increases static orofacial allodynia

The Journal of Headache and Pain

Research Article

Omar Ouachikh¹  Sofia Alves¹  Aziz Hafidi¹  Franck Durif²  Yves Boucher³  Wisam Dieb⁴ 

[1] Clermont Université, Université d’Auvergne, EA7280, Clermont-Ferrand, France;Clermont Université, Université d’Auvergne, EA7280, Clermont-Ferrand, France;CHU Clermont-Ferrand, Service de Neurologie, 63000, Clermont-Ferrand, France;UFR Odontologie, Université Paris Diderot, Paris, France;Centre de Psychiatrie et Neurosciences, INSERM U894, Paris, France;UFR Odontologie, Université Paris Diderot, Paris, France;Centre de Psychiatrie et Neurosciences, INSERM U894, Paris, France;Clermont Université, Université d’Auvergne, EA7280, Clermont-Ferrand, France;

关键词: Parkinson disease;    Dopamine;    Pain;    Substantia nigra;    Chronic constriction injury;    Neuropathic pain;    Infraorbitary nerve;   

DOI  :  10.1186/s10194-016-0607-z

 received in 2015-09-30, accepted in 2016-02-12,  发布年份 2016

来源: Springer

【 摘 要 】

BackgroundThis study investigated mesencephalic dopamine depletion effects on static mechanical allodynia (SMA) elicited by chronic constriction of the infraorbitary nerve (CCI-IoN).MethodsDopamine depletion (6-OHDA administration into the medial forebrain bundle) effects on CCI-IoN-induced SMA were explored using behavioral (nocifensive behavior score upon non-noxious stimuli using von Frey filament), pharmacological (bromocriptine injections) and immunohistochemical (PKCγ and pERK1/2) techniques.ResultsThe central dopamine depletion increased significantly the SMA score. Intraperitoneal and intracisternal injections of bromocriptine alleviated the allodynic behavior observed in both CCI-IoN and CCI-IoN + 6-OHDA animal groups. At the cellular level, dopamine depletion induced a significant increase in PKCγ expression in the medullary dorsal horn (MDH) in rat with CCI-IoN + 6-OHDA when compared to sham animals (CCI-IoN only). Similarly, after static non-noxious stimuli, the expression of pain marker proteins pERK1/2 within the MDH revealed significantly a higher number of positive cells in CCI-IoN + 6-OHDA rats when compared to the CCI-IoN group.ConclusionThis study demonstrates that nigrostriatal dopamine depletion exacerbates the neuropathic pain resulting from CCI-IoN. This effect is probably due to an action through descending pain inhibitory systems which increased pain sensitization at the MDH level. It demonstrates also an analgesic effect elicited by D2R activation at the segmental level.

【 授权许可】

CC BY   
© Dieb et al. 2016