目的 ·观察二氢杨梅素（ dihydromyricetin，DMY）对类风湿性关节炎模型大鼠脾脏免疫功能的调节作用。方法 ·将 30只 Wistar大鼠随机分为 5组，分别为正常组、模型组和 DMY给药组（给药剂量分别为 5、25和 50 mg/kg），模型组和 DMY给药组建立Ⅱ型胶原诱导的类风湿性关节炎（ type Ⅱ collagen-induced rheumatoid arthritis，CIA）大鼠模型； DMY给药组按设定剂量腹腔注射 DMY，每 2日注射 1次。给药 5周后，处死各组大鼠，取出脾脏，制作组织切片，苏木精 -伊红染色后观察病理变化。分离模型组脾淋巴细胞， CCK8试剂盒检测 DMY在体外对炎症状态下脾淋巴细胞增殖的影响；流式细胞术检测 T淋巴细胞不同亚群的百分含量；PCR和 ELISA测定脾淋巴细胞相关炎症因子的表达情况。结果 ·与模型组相比， DMY给药组脾脏的炎症相关病理变化明显缓解。 DMY在体外可抑制伴刀豆球蛋白（ ConA）诱导的脾淋巴细胞增殖，减少 ConA引起的 CD3+CD4+细胞百分比增加，高浓度时可略增加 CD3+CD8+细胞百分比。 PCR和 ELISA结果表明， DMY在体内外条件下均可抑制脾淋巴细胞促炎因子的表达，同时促进抗炎因子的表达。结论 · DMY在体内和体外均对 CIA模型大鼠脾脏中免疫相关 T淋巴细胞具有免疫调节作用，从而抑制全身性炎症反应。

Objective · To investigate the immunoregulatory effect of dihydromyricetin (DMY) on the spleens of rats with rheumatoid arthritis. Methods · Thirty Wistar rats were randomly divided into five groups, i.e., normal group, model group and DMY administration groups (5, 25, and 50 mg/kg). The type Ⅱ collagen-induced rheumatoid arthritis (CIA) model was established in model group and DMY administration groups. DMY administration groups were intraperitoneally injected with DMY every other day at set doses. After five weeks of administration, rats of each group were sacrificed, and the spleens were taken out to prepare tissue sections, and pathological changes were observed after hematoxylin-eosin staining. The spleen lymphocytes of model group were isolated, and the effect of DMY on the proliferation of spleen lymphocytes in inflammatory state was detectedcell-counting-kit 8. The percentages of different subsets of T lymphocytes were detectedflow cytometry. The of inflammatory factors in spleen lymphocytes was determinedPCR and ELISA. Results · Compared with model group, inflammation-related pathological changes in the spleens of DMY-administered groups were significantly relieved. DMY could inhibit the proliferation of spleen lymphocytes, reduce the percentage of CD3+CD4+ cells and slightly increase the percentage of CD3+CD8+ cells after the treatment of concanavalin (ConA) in vitro. The results of PCR and ELISA showed that DMY could inhibit the of proinflammatory cytokines and promote the of anti-inflammatory factors both in vitro and in vivo. Conclusion · DMY has immunomodulatory effects on immune-associated T lymphocytes in the spleens of CIA rats in vivo and in vitro, thereby inhibiting systemic inflammatory response.