Department of Physical Therapy Science, Nagasaki University Graduate School of Biomedical Sciences, Sakamoto 1-7-1, Nagasaki, 852-8520, Japan.
Department of Physical Therapy Science, Nagasaki University Graduate School of Biomedical Sciences, Sakamoto 1-7-1, Nagasaki, 852-8520, Japan.
Neurosci Lett. 2019 Jul 27;706:18-23. doi: 10.1016/j.neulet.2019.04.031. Epub 2019 Apr 24.
We examined the effect of immobilization, low-intensity muscle contraction exercise, and transcutaneous electrical nerve stimulation (TENS) on tissue inflammation and acute pain following the onset of arthritis in a rat model. Sixty Wistar rats were divided into five groups: (1) Arthritis group, (2) arthritis and immobilization (Immobilization group), (3) arthritis and low intensity muscle contraction (Exercise group), (4) arthritis and TENS (TENS group), and (5) sham arthritis (Sham group). Arthritis was induced in the right knee joints by single injection of 3% kaolin and carrageenan. Immobilization of the right hindlimb was conducted by full extension of the right knee joints and full plantar flexion of the ankle joints using a plaster cast for 7 days after injection. The right quadriceps muscles were subjected to electrical stimulation (frequency: 50 Hz; intensity: 2-3 mA) for 20 min/day as contraction exercise for one week. TENS was delivered at 20 min/day for one week (frequency: 50 Hz; intensity: 1 mA). The pressure pain threshold (PPT) and paw withdrawal response (PWR) were evaluated at 1 and 7 days after injection. We also analyzed the number of CD68-positive cells in the synovium by immunohistochemistry and determined the expression level of calcitonin gene-related peptide (CGRP) in the spinal dorsal horn with immunofluorescence. Improvements of both PPT and PWR were observed in the Exercise group at 7 days after injection compared to those of the Arthritis and Immobilization groups, although only improvement of PPT was observed in the TENS group. The number of CD68-positive cells in the synovium and CGRP expression in the dorsal horn decreased only in the Exercise group. These results suggested that low-intensity muscle contraction exercise might be a better treatment for reduction of arthritis-induced inflammation and acute pain compared to immobilization and TENS.
我们研究了固定、低强度肌肉收缩运动和经皮电神经刺激（TENS）对关节炎大鼠模型中关节炎发作后组织炎症和急性疼痛的影响。将 60 只 Wistar 大鼠分为五组：（1）关节炎组，（2）关节炎和固定组（固定组），（3）关节炎和低强度肌肉收缩组（运动组），（4）关节炎和 TENS 组（TENS 组）和（5）假关节炎组（假关节炎组）。通过单次注射 3%的高岭土和角叉菜胶在右膝关节诱导关节炎。关节炎注射后第 7 天，用石膏固定完全伸展右膝关节和完全跖屈踝关节，对右后肢进行固定。右股四头肌每天接受电刺激（频率：50 Hz；强度：2-3 mA）20 分钟，进行为期一周的收缩运动。TENS 每天 20 分钟，持续一周（频率：50 Hz；强度：1 mA）。注射后第 1 天和第 7 天，评估压力疼痛阈值（PPT）和足爪回缩反应（PWR）。我们还通过免疫组织化学分析滑膜中 CD68 阳性细胞的数量，并通过免疫荧光测定脊髓背角中降钙素基因相关肽（CGRP）的表达水平。与关节炎和固定组相比，运动组在注射后第 7 天 PPT 和 PWR 均有改善，而 TENS 组仅观察到 PPT 改善。滑膜中 CD68 阳性细胞的数量和背角中 CGRP 的表达仅在运动组中减少。这些结果表明，与固定和 TENS 相比，低强度肌肉收缩运动可能是减轻关节炎引起的炎症和急性疼痛的更好治疗方法。
