European journal of pain : EJP
-
Mounting evidence points to individual contributions of tumour necrosis factor-alpha (TNF) and the c-Jun N-terminal kinase (JNK) pathway to the induction and maintenance of various pain states. Here we explore the role of spinal TNF and JNK in carrageenan-induced hypersensitivity. As links between TNF and JNK have been demonstrated in vitro, we investigated if TNF regulates spinal JNK activity in vivo. ⋯ Here we show that spinal JNK activity is dependent on TNF and that both TNF and the JNK signalling pathways modulate pain-like behaviour induced by peripheral inflammation.
-
Although visceral hypersensitivity is a major pathophysiological feature of irritable bowel syndrome (IBS), its underlying mechanisms remain elusive. Toll-like receptor 4 (TLR4) is a critical pattern recognition molecule of the innate immune system. In this study, we investigated whether the TLR4/myeloid differentiation factor 88 (MyD88)/nuclear factor-kappa B (NF-κB) signalling pathway in the spinal cord contributed to the visceral hypersensitivity induced by neonatal colonic irritation (CI) in rats. ⋯ These results suggest that neonatal CI stimulates the production of IL-1β and TNF-α through the TLR4/MyD88/NF-κB signalling pathway in the spinal cord, which contributed to visceral hypersensitivity induced by neonatal CI in rats.
-
Recent research suggests that anxiety sensitivity (AS) may be a critical factor in the maintenance of chronic pain. Converging lines of evidence also propose a relationship between AS and fear of pain (FOP) that may result from interoceptive fear conditioning in interoceptively biased individuals. While some AS and FOP research has been carried out in adults, literature exploring this relationship is sparse in clinical paediatric populations. ⋯ These results provide evidence for the pivotal role of AS in the paediatric chronic pain model. The findings of this study further emphasize the application of the fear-avoidance model in children and provide new evidence for the critical role of AS in a paediatric headache population.
-
The application to the skin of spatially interlaced innocuous warm (40 °C) and cool (20 °C) thermodes (termed a thermal grill--TG) can produce an unusual thermal percept, but the mechanisms remain unclear. ⋯ The TG percept intensity and temporal profile were different from those evoked by either of its component parts. The perceived quality is person-specific. These differences suggest that the classic 'TG illusion' results from complex central integration of several types of peripheral afferent inputs activated by the TG. Differing body site-related roles of thermosensory afferents in discrimination versus temperature homeostasis may explain site-related variations in the percept.
-
Randomized Controlled Trial
Validating speed of onset as a key component of good analgesic response in acute pain.
Previous analysis of a single data set in acute pain following third molar extraction demonstrated a strong relationship between the speed of reduction of pain intensity and overall pain relief, as well as need for additional analgesia. ⋯ In acute pain following third molar extraction, faster acting analgesic formulations provide earlier onset of pain relief, better overall pain relief and a less frequent need for additional analgesia, indicating longer lasting pain relief.