European journal of pain : EJP
-
The higher order processes involved in self-regulation are generally thought to depend on cognitive (attentional/executive) functions with limited resources. Experimental studies further show that exerting self-control in a first task results in decreased performance in other following self-control tasks, which may be interpreted as the consequence of either effective or perceived resource depletion outlasting the first task. Given that higher order cognitive/attentional processes are also considered to be involved in pain modulatory mechanisms, we tested the idea that pain could be influenced by prior mobilization of cognitive resources. ⋯ These findings suggest that pain regulation mechanisms including the descending pain modulatory system may be less efficient after the performance of tasks requiring high cognitive control resulting in stronger pain experience.
-
Nerve injury leads to Aβ-fibre-mediated mechanical allodynia that is in part due to an impaired GABAergic inhibition in the spinal cord dorsal horn. The properties and function of GABAergic neurons in spinal cord lamina III, an area where low-threshold mechanosensitive Aβ-fibres terminate are, however, largely unknown. ⋯ A change in membrane excitability or discharge pattern of this group of lamina III GABAergic neurons is unlikely the cause for mechanical allodynia in animals with CCI.
-
Platelet-activating factor (PAF) has been implicated in the pathology of neuropathic pain. Previous studies reported that PAF receptor (PAF-R) antagonists have varied anti-allodynia effects by route of administration and nerve injury models in rats. ⋯ The present results revealed the effectiveness in anti-allodynia of PAF antagonists in different nerve injury models, and the unique mode of action; long-lasting anti-allodynia effects mediated by spinal GlyRα3 with a competitive manner at the initial stage and the following non-competitive manner of inhibition.
-
Previous studies have identified neuromedin U receptor 2 (NMUR2) as the subtype mediating the effects of neuromedin U on acute chemo-nociception induced by capsaicin or formalin injection. The aims of this study were to determine whether NMUR2 is required for the development of mechanical hypersensitivity after nerve injury or heat hypersensitivity after inflammation and whether there is a gender difference in the contribution of NMUR2 to nociception. ⋯ The present data do not support a significant contribution of NMUR2 to the development of hypersensitivity after nerve injury or tissue inflammation, suggesting that pharmacological intervention aimed at the NMUR2 receptor might not be a valuable approach for the treatment of chronic pain.
-
Identification of prognostic factors for surgery in patients with sciatica is important to be able to predict surgery in an early stage. Identification of prognostic factors predicting persistent pain, disability and recovery are important for better understanding of the clinical course, to inform patient and physician and support decision making. Consequently, we aimed to systematically review prognostic factors predicting outcome in non-surgically treated patients with sciatica. ⋯ Reported evidence regarding prognostic factors predicting the outcome in sciatica is limited. The majority of factors that have been evaluated, e.g., age, body mass index, smoking and sensory disturbance, showed no association with outcome. The only positive association with strong evidence was found for leg pain intensity at baseline as prognostic factor for subsequent surgery.