目的  构建小鼠坐骨神经损伤（SNI）模型，探讨人参皂苷Rb1对小鼠坐骨神经损伤修复的促进作用及机制。   方法  选取成年雄性昆明小鼠78只，随机分为假手术组（26只）、模型组（26只）、治疗组（26只）。模型制作采用钳夹损伤法，假手术组仅游离坐骨神经。模型制作后30 min，治疗组腹腔注射10 mg/kg人参皂苷Rb1，模型组与假手术组给予同等体积的生理盐水。采用坐骨神经功能指数（SFI）对小鼠坐骨神经功能进行追踪评价；利用HE染色及生长相关蛋白43(GAP43)免疫荧光染色检测损伤14 d后坐骨神经再生修复情况；利用透射电子显微镜观察损伤节段髓鞘的结构改变。损伤后14 d，检测脑源性神经营养因子(BDNF)、神经生长因子(NGF)mRNA水平的表达变化。模型制作后3 d、7 d，利用Ki67、S100β免疫荧光染色检测施万细胞的增殖、迁移能力；利用Real-time PCR检测炎症相关因子以及施万细胞激活相关转录因子mRNA表达水平；通过Western blotting对Sox10在蛋白水平的变化进行验证。   结果  治疗组SFI评分高于模型组小鼠，神经近端、远端HE染色较均一。透射电子显微镜提示，治疗组髓鞘结构、厚度较模型组明显改善，髓鞘内神经纤维排列较为整齐。免疫荧光染色结果显示，治疗组坐骨神经GAP43+轴突伸长明显优于模型组，BDNF、NGF等营养因子表达升高。进一步检测发现，给予Rb1后损伤节段附近Ki67+细胞增殖、S100β+施万细胞迁移明显增多。Real-time PCR结果显示，治疗组肿瘤坏死因子(TNF)-α、白细胞介素(IL)-1β mRNA表达水平明显下降，施万细胞激活相关转录因子表达水平上升。   结论  10 mg/kg Rb1能降低再生组织环境中炎症因子表达水平，增加BDNF、NGF等营养因子的表达水平，促进施万细胞激活，从而促进小鼠坐骨神经损伤后的神经再生。 

Objective  To explore the effect and mechanism of ginsenoside Rb1 on the repair of sciatic nerve injury (SNI) in mice.    Methods  Seventy-eight adult male Kunming mice were randomly divided into sham group (26), SNI group (26), SNI+Rb1 group (26). The SNI+Rb1 group was given 10 mg/kg ginsenoside Rb1 (i.p.), and the SNI group and the sham group were given the same volume of normal saline. The injury method  was established by squeezing the sciatic nerve. Sciatic functional index (SFI) was used to evaluate sciatic nerve function. Growth associated protein 43(GAP43) immunofluorescent staining was used to detect neural regeneration and repair on day 14, and the structure changes of the myelin sheath of the injured segment were observed under transmission electron microscope. Ki67 and S100β were used to detect the proliferation and migration ability of Schwann cells, and Real-time PCR was used to detect the mRNA expression levels after crush on day 3 and day 7.   Results SFI of SNI+Rb1 group was higher than SNI group. The HE result  showed that the sciatic nerve was uniform in the SNI+Rb1 group. The result  of immunofluorescent staining displayed that Rb1 enhanced GAP43+ axon elongation, and the expression of brain derived neurotrophic factor (BDNF), nerve growth factor (NGF) was elevated. Transmission electron microscopy study suggested that, compared with the model group, the myelin structure and thickness of the SNI+Rb1 group were improved. Further testing revealed that Ki67+ cell proliferation and S100β+ Schwann cell migration in the vicinity of the injured segment increased after Rb1 was administered. The result  of Real-time PCR showed that the mRNA expression levels of tumor necrosis factor (TNF)-α and interleukin (IL)-1β in the SNI+Rb1 group decreased rapidly, and the expression levels of transcription factors related to Schwann cell activation increased (P<0.05).    Conclusion  Rb1 10 mg/kg can reduce the expression level of inflammatory factors, and increase the expression level of BDNF and NGF, and promote Schwann cell activation, which is beneficial for the nerve regeneration after sciatic nerve injury in mice.