Mojadadi Mohammad-Shafi, Amin Bahareh, Zeinali Hossein, Nazemi Samad
Department of Immunology, School of Medicine, Sabzevar University of Medical Sciences, Sabzevar, Iran.
Department of Physiology and Pharmacology, School of Medicine, Sabzevar University of Medical Sciences, Sabzevar, Iran.
Physiol Rep. 2025 Apr;13(8):e70318. doi: 10.14814/phy2.70318.
Neuropathic pain (NP) arises from nerve damage or compression and often extends to the contralateral side of the body (mirror-image pain, MP) and adjacent non-injured areas (extraterritorial pain). This study investigates whether altered sensitivity in these contralateral and peripheral regions is mediated by glial cells, using the chronic constriction injury (CCI) model of NP. Thirty-two male Wistar rats were randomly assigned into four groups (8/group): sham, CCI + vehicle, CCI + minocycline (MIN;10 mg/kg), and CCI + pentoxifylline (PTX;8 mg/kg). The CCI model was employed for NP induction. MIN and PTX were administered intraperitoneally from postoperative days (POD)4 to POD14, once daily. Pain responses were assessed on POD0, 2, 6, 10, and14 using Hargreaves, von Frey, and Tail-flick tests. Western blot analysis was performed on POD14 to measure Iba1 and GFAP protein expression in the spinal cord hemispheres. Results revealed that post-injury treatment with MIN and PTX significantly reduced contralateral thermal hyperalgesia, mechanical allodynia, and tail-flick responses. Correspondingly, the contralateral spinal cord exhibited significantly decreased GFAP and Iba1 protein expression compared to the CCI + vehicle treated group. These findings suggest that post-injury glial cell inhibition effectively mitigates neuropathic pain and prevents the development of MP and extraterritorial pain. This highlights the potential for clinical applications targeting glial cells to manage NP even after nerve injury.
神经性疼痛(NP)源于神经损伤或受压,且常扩散至身体的对侧(镜像疼痛,MP)和相邻的未损伤区域(域外疼痛)。本研究使用NP的慢性压迫损伤(CCI)模型,探究这些对侧和外周区域的敏感性改变是否由胶质细胞介导。32只雄性Wistar大鼠被随机分为四组(每组8只):假手术组、CCI + 溶剂组、CCI + 米诺环素(MIN;10 mg/kg)组和CCI + 己酮可可碱(PTX;8 mg/kg)组。采用CCI模型诱导NP。从术后第4天(POD)至第14天,每天一次腹腔注射MIN和PTX。在POD0、2、6、10和14使用热辐射甩尾试验、von Frey试验和尾甩试验评估疼痛反应。在POD14进行蛋白质免疫印迹分析,以测量脊髓半球中Iba1和GFAP蛋白的表达。结果显示,损伤后用MIN和PTX治疗可显著减轻对侧热痛觉过敏、机械性异常性疼痛和尾甩反应。相应地,与CCI + 溶剂治疗组相比,对侧脊髓中GFAP和Iba1蛋白表达显著降低。这些发现表明,损伤后抑制胶质细胞可有效减轻神经性疼痛,并预防MP和域外疼痛的发生。这突出了针对胶质细胞进行临床应用以治疗NP(即使在神经损伤后)的潜力。