@misc{10498/33329,
year = {2013},
month = {1},
url = {http://hdl.handle.net/10498/33329},
abstract = {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.},
publisher = {Elsevier},
keywords = {α2-adrenoceptors},
keywords = {depression},
keywords = {locus coeruleus},
keywords = {neuropathic pain},
keywords = {noradrenaline},
keywords = {prefrontal cortex},
title = {Chronic pain leads to concomitant noradrenergic impairment and mood disorders},
doi = {10.1016/j.biopsych.2012.06.033},
author = {Alba Delgado, Cristina and Llorca Torralba, Meritxell and Horrillo, Igor and Ortega, Jorge E. and Micó Segura, Juan Antonio and Sánchez-Blázquez, Pilar and Meana, Javier and Berrocoso Domínguez, Esther María},
}