目的 探究二仙丸基于“得温痛减”治疗类风湿关节炎疼痛的疗效和作用机制。方法 构建胶原诱导型关节炎（CIA）模型大鼠并ig给予低、高剂量（0.45、0.90 g·kg^-1）二仙丸和雷公藤多苷片（阳性药，9.45 mg·kg^-1）治疗，观察对体质量、关节外观、关节炎评分的影响；进行足底机械疼痛阈值、足底热痛潜伏时间测定； Micro-CT检测踝关节影像学变化； ELISA检测血清炎症因子白细胞介素（IL）-1β、IL-6、IL-10、IL-4水平；进行踝关节苏木精-伊红（HE）染色、Masson染色；实时荧光定量PCR（qRT-PCR）检测组织中TRPV1、CGRP基因转录的变化；采用Western blotting检测关节和脊髓中降钙素基因相关肽（CGRP）、瞬时受体电位香草酸亚型1（TRPV1）及c-fos蛋白的表达；免疫荧光染色检测脊髓组织c-fos蛋白表达水平。结果 与对照组相比，CIA大鼠均体质量降低（P＜0.01），关节炎评分显著升高（P＜0.01）；足爪发生红肿，机械撤退阈值和热痛潜伏时间均降低（P＜0.01），滑膜增生、骨表面粗糙侵蚀；血清促炎因子（IL-1β、IL-6）增加、抑炎因子（IL-10、IL-4）减少（P＜0.01）；踝关节中TRPV1和CGRP蛋白表达量均显著增加（P＜0.01）；脊髓CGRP基因转录水平和CGRP、c-fos蛋白表达量显著升高（P＜0.01），TRPV1蛋白表达呈升高趋势；脊髓背角处的c-fos荧光强度明显增强。与模型组比较，二仙丸高剂量组大鼠体质量显著增加（P＜0.01），关节炎评分显著降低（P＜0.01）；关节肿胀、滑膜增生减轻，并且蓝色胶原纤维沉积明显减轻；机械撤退阈值和热痛潜伏时间均显著增加（P＜0.01）；血清炎症因子释放减少、抑炎因子增加（P＜0.01）；关节和脊髓中CGRP、TRPV1、c-fos蛋白表达降低（P＜0.05、0.01）；脊髓CGRP基因转录水平显著降低（P＜0.01）； c-fos荧光强度明显降低。结论 二仙丸能有效改善CIA大鼠关节炎症和疼痛阈值，可能与抑制TRPV1减轻痛觉敏化有关，为中医“得温痛减”理论提供科学参考。

Objective To investigate the efficacy and mechanism of Erxian Pill (EXP) in treating pain of rheumatoid arthritis based on the principle of “decreased pain upon warmth”. Methods A collagen-induced arthritis (CIA) rat model was established, and rats were administered low-and high-dose Erxian Pills (0.45 and 0.90 g·kg^-1, respectively) or tripterygium glycosides tablets (positive control, 9.45 mg·kg^-1) via oral gavage. Body weight, joint appearance, and arthritis scores were assessed. Mechanical withdrawal threshold and thermal pain latency in the hindpaws were measured. Micro-CT was used to evaluate ankle joint imaging changes. Serum levels of inflammatory cytokines—interleukin (IL)-1β, IL-6, IL^-10, and IL-4—were detected by ELISA. Hematoxylin-eosin (HE) and Masson staining were performed on ankle joints. Real-time quantitative PCR (qRT-PCR) analyzed transcriptional changes of TRPV1 and CGRP genes in tissues. Western blotting examined protein expression of calcitonin gene-related peptide (CGRP), transient receptor potential vanilloid subtype 1 (TRPV1), and c-fos in joints and spinal cord. Immunofluorescence staining assessed c-fos protein expression in spinal cord tissue. Results Compared with the control group, CIA rats showed reduced body weight (P<0.01), significantly elevated arthritis scores (P<0.01), redness and swelling of paws, decreased mechanical withdrawal threshold and thermal pain latency (P<0.01), synovial hyperplasia, and roughened bone surfaces with erosion. Serum pro-inflammatory factors (IL^-1β, IL-6) increased while anti-inflammatory factors (IL^-10, IL-4) decreased (P<0.01). Expression of TRPV1 and CGRP proteins in the ankle joints was significantly upregulated (P<0.01). In the spinal cord, CGRP gene transcription and CGRP and c-fos protein expression were markedly elevated (P<0.01), while TRPV1 protein expression showed an increasing trend. Fluorescence intensity of c-fos in the dorsal horn of the spinal cord was significantly enhanced. Compared with the model group, rats treated with high-dose Erxian Pills exhibited significant increases in body weight (P<0.01) and marked reductions in arthritis scores (P<0.01). Joint swelling and synovial hyperplasia were alleviated, and blue collagen fiber deposition was notably reduced. Mechanical withdrawal threshold and thermal pain latency were significantly improved (P<0.01). Serum inflammatory factor release decreased, while anti-inflammatory factors increased (P<0.01). Protein expression of CGRP, TRPV1, and c-fos in both joints and spinal cord was downregulated (P<0.05, 0.01). CGRP gene transcription in the spinal cord was significantly reduced (P<0.01), and c-fos fluorescence intensity was markedly decreased. Conclusion Erxian Pills effectively ameliorate joint inflammation and pain thresholds in CIA rats, likely through suppression of TRPV1-mediated pain sensitization, providing scientific support for the TCM theory that “warmth reduces pain”.

R965

国家自然科学基金资助项目（82405534）；博士科研启动基金资助项目（2023BK16，2023BKS19）；山西省中管局科研课题计划项目（2022ZYYC269）；中西医结合治疗风湿免疫病重点研究室（zyyyjs2024021）；山西省经方扶阳重点研究室（202104010910011）