A1型反应性星形胶质细胞在神经病理性疼痛大鼠脊髓的表达特点

THE EXPRESSION OF A1 REACTIVE ASTROCYTES IN SPINAL CORD IN RATS WITH NEUROPATHIC PAIN

摘要:

目的 观察神经病理性疼痛大鼠脊髓中A1型反应性星形胶质细胞的表达变化，为进一步明确星形胶质细胞亚型在神经病理性疼痛形成中的作用提供依据。方法 雄性SD大鼠24只，随机分为假手术组和神经病理性疼痛组（SNL组）。采用脊神经结扎法建立神经病理性疼痛模型。在术前1d、术后1d、3d、7d、14d分别测量各组大鼠机械缩足阈值的变化，于术后7d免疫组化检测脊髓背角c-fos和GFAP的表达，采用免疫荧光双标检测GFAP和C3的共表达，于术后3d、7d、14d采用实时定量PCR检测脊髓A1型反应性星形胶质细胞的标志物C3的表达。结果 与假手术组相比，SNL组术后机械痛阈值降低，且术后7d免疫组化显色脊髓背角c-Fos和GFAP表达均升高，证明神经病理性疼痛模型构建成功；SNL组术后7d免疫荧光双标证实C3和GFAP共表达；与假手术组相比，术后3d、7d、14d SNL组脊髓背角C3的mRNA水平表达增加。结论 神经病理性疼痛大鼠脊髓背角A1型反应性星形胶质细胞明显增加，提示A1型反应性星形胶质细胞可能参与了神经病理性疼痛的发生发展。

Abstract:

Objective: The purpose of this study is to investigate the expression of A1 reactive astrocytes in spinal cord in rats with neuropathic pain. It will be helpful for further understanding the role of reactive astrocyte subtypes in the neuropathic pain. Methods: A total of 24 male SD rats weighing 180-220g were randomly divided into sham group and neuropathic pain group (SNL group) The neuropathic pain model was established by spinal nerve ligation. The 50% mechanical withdrawal threshold of the left foot of the rat was assessed with von Frey filaments at different time points using Up and Down methods. The expression of c-fos and GFAP in spinal dorsal horn was detected by immunohistochemistry on 7th day after operation. The co-expression of GFAP and C3 was detected by double immunofluorescent labeling. The change of C3 mRNA expression was examined by real time RT-PCR on 3rd,7th,14th day after operation. Results: Compared with the sham group, the mechanical pain threshold in SNL group was lower after operation. The expression of c-Fos and GFAP in the dorsal horn of spinal cord was increased on 7th day after operation. These indicated that the neuropathic pain model was successfully constructed. The co expression of C3 and GFAP in SNL group was confirmed by double immunofluorescent labeling. Compared with sham group, the expression of C3 mRNA in spinal dorsal horn in SNL group was increased on 3rd, 7th, 14th day after operation. Conclusion: The number of A1 reactive astrocytes in the spinal dorsal horn of rats with neuropathic pain is significantly increased, suggesting that A1 reactive astrocytes may be involved in the occurrence and development of neuropathic pain.