Pain
-
Meta Analysis
NEUROMUSCULAR ADAPTATIONS TO EXPERIMENTALLY INDUCED PAIN IN THE LUMBAR REGION: SYSTEMATIC REVIEW AND META-ANALYSIS.
Experimental pain models are frequently used to understand the influence of pain on the control of human movement. In this systematic review, we assessed the effects of experimentally induced pain in the lumbar region of healthy individuals on trunk muscle activity and spine kinematics. Databases were searched from inception up to January 31, 2022. ⋯ By contrast, activity of erector spinae, deep multifidus, and transversus abdominis was reduced during postural perturbation tasks. Reduced range of motion of the lumbar spine in the presence of pain was supported by low quality of evidence. Given the agreement between our findings and the adaptations observed in clinical populations, the use of experimental pain models may help to better understand the mechanisms underlying motor adaptations to low back pain.
-
Repeated stress produces hyperalgesic priming in preclinical models, but underlying mechanisms remain uncertain. As stress engages kappa opioid receptors (KORs), we hypothesized that repeated administration of KOR agonists might mimic, in part, stress-induced hyperalgesic priming. The potential contribution of circulating prolactin (PRL) and dysregulation of the expression of PRL receptor (PRLR) isoforms in sensory neurons after KOR agonist administration was also investigated. ⋯ Umbellulone-induced allodynia was prevented by cabergoline co-treatment during priming with KOR agonists in female, but not male, mice. Hyperalgesic priming therefore occurs in both sexes after either biased or nonbiased KOR agonists. However, a PRL/PRLR-dependence is observed only in female nociceptors possibly contributing to pain in stress-related pain disorders in females.
-
Specialized proresolving mediators (SPMs) have demonstrated potent analgesic actions in animal models of pathological pain. The actions of SPMs in acute and chronic itch are currently unknown. Recently, n-3 docosapentaenoic acid (DPA) was found to be a substrate for the biosynthesis of several novel families of SPMs and 3-oxa-PD1 n-3 DPA (3-oxa-PD1) is an oxidation-resistant metabolic stable analogue of the n-3 DPA-derived protectin D1 (PD1). ⋯ Finally, CTCL-induced anxiety was alleviated by intrathecal 3-oxa-PD1. Our findings suggest that 3-oxa-PD1 potently inhibits acute and chronic itch through the regulation of excitatory or inhibitory synaptic transmission and astroglial LCN2 production. Therefore, stable SPM analogs such as 3-oxa-PD1 could be useful to treat pruritus associated with different skin injuries.
-
The purpose of this study was to further our understanding of early childhood pain-related distress regulation. Concurrent and predictive relations between child-led emotion regulation (ER) behaviors and pain-related distress during vaccination were examined at 2 different ages using autoregressive cross-lagged path analyses. Toddlers were video-recorded at the 12- and 18-month routine vaccination appointments (12-month-old [N = 163]; 18-month-old [N = 149]). ⋯ Physical self-soothing was significantly related to less pain-related distress at both ages. Taken together, these findings suggest that disengagement of attention and physical self-soothing may serve more of a regulatory function during toddlerhood, whereas parent-focused behaviors may serve more of a function of gaining parent support for regulation. This study is the first to assess these relations during routine vaccination in toddlerhood and suggests that toddlers in the second year of life are beginning to play a bigger role in their own regulation from painful procedures than earlier in infancy.