RT journal article
T1 Chronic pain leads to concomitant noradrenergic impairment and mood disorders
A1 Alba Delgado, Cristina
A1 Llorca Torralba, Meritxell
A1 Horrillo, Igor
A1 Ortega, Jorge E.
A1 Micó Segura, Juan Antonio
A1 Sánchez-Blázquez, Pilar
A1 Meana, Javier
A1 Berrocoso Domínguez, Esther María
A2 Anatomía PatológicaBiología Celular, Histología, Historia de la Ciencia, Medicina Legal y Forense y Toxicología
A2 Neurociencias
A2 Psicología
K1 α2-adrenoceptors
K1 depression
K1 locus coeruleus
K1 neuropathic pain
K1 noradrenaline
K1 prefrontal cortex
AB Background: Patients suffering chronic pain are at high risk of suffering long-lasting emotional disturbances characterized by persistent low mood and anxiety. We propose that this might be the result of a functional impairment in noradrenergic circuits associated with locus coeruleus (LC) and prefrontal cortex, where emotional and sensorial pain processes overlap.Methods: We used a chronic constriction injury of sciatic nerve as a model of neuropathic pain in male Sprague-Dawley rats to assess the time-dependent changes that might potentially precipitate mood disorders (2, 7, 14, and 28 days after injury). This was measured through a combination of behavioral, electrophysiological, microdialysis, immunohistochemical, and Western blot assays.Results: As expected, nerve injury produced an early and stable decrease in sensorial pain threshold over the testing period. By contrast, long-term neuropathic pain (28 days after injury) resulted in an inability to cope with stressful situations, provoking depressive and anxiogenic-like behaviors, even more intense than the aversiveness associated with pain perception. The onset of these behavioral changes coincided with irruption of noradrenergic dysfunction, evident as: an increase in LC bursting activity; in tyrosine hydroxylase expression and that of the noradrenaline transporter; and enhanced expression and sensitivity of α2-adrenoceptors in the LC.Conclusions: Long-term neuropathic pain leads to anxio-depressive-like behaviors that are more predominant than the aversion of a painful experience. These changes are consistent with the impairment of noradrenergic system described in depressive disorders.
PB Elsevier
SN 0006-3223
YR 2013
FD 2013-01-01
LK http://hdl.handle.net/10498/33329
UL http://hdl.handle.net/10498/33329
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 21-sep-2026