1 Department of Orthopaedic Surgery, Tohoku University Graduate School of Medicine, Sendai, Japan.
2 Department of Nursing, Tohoku Fukushi University, Sendai, Japan.
Mol Pain. 2018 Jan-Dec;14:1744806918757286. doi: 10.1177/1744806918757286. Epub 2018 Jan 21.
Muscle pain is a common condition that relates to various pathologies. Muscle overuse induces muscle pain, and neutrophils are key players in pain production. Neutrophils also play a central role in chronic pain by secreting interleukin (IL)-18. The aim of this study was to investigate the involvement of neutrophils and IL-18 in a mouse model of muscle pain. The right hind leg muscles of BALB/c mice were stimulated electrically to induce excessive muscle contraction. The left hind leg muscles were not stimulated. The pressure pain threshold, number of neutrophils, and IL-18 levels were investigated. Furthermore, the effects of the IL-18-binding protein and Brilliant Blue G on pain were investigated. In stimulated muscles, pressure pain thresholds decreased, and neutrophil and IL-18 levels increased compared with that in non-stimulated muscles. The administration of IL-18-binding protein and Brilliant Blue G attenuated hyperalgesia caused by excessive muscle contraction. These results suggest that increased IL-18 secretion from larger numbers of neutrophils elicits mechanical hyperalgesia.
肌肉疼痛是一种常见病症，与多种病理有关。肌肉过度使用会引起肌肉疼痛，而中性粒细胞是产生疼痛的关键因素。中性粒细胞通过分泌白细胞介素 (IL)-18 在慢性疼痛中也起着核心作用。本研究旨在探讨中性粒细胞和 IL-18 在肌肉疼痛小鼠模型中的作用。使用电刺激 BALB/c 小鼠的右后肢肌肉以诱导过度肌肉收缩，而左后肢肌肉则不进行刺激。研究了压力疼痛阈值、中性粒细胞数量和 IL-18 水平。此外，还研究了白细胞介素-18 结合蛋白和亮蓝 G 对疼痛的影响。与非刺激肌肉相比，在刺激肌肉中，压力疼痛阈值降低，中性粒细胞和 IL-18 水平升高。白细胞介素-18 结合蛋白和亮蓝 G 的给药可减轻过度肌肉收缩引起的痛觉过敏。这些结果表明，更多数量的中性粒细胞分泌增加的 IL-18 会引起机械性痛觉过敏。
