目的    研究消炎止痛膏对脂多糖诱导的C2C12肌管的作用机制。  方法    体外培养C2C12细胞，用2%马血清诱导分化C2C12为成熟肌管，设置空白组、模型组、双氯芬酸钠组、消炎止痛膏组。非空白组加入不同浓度脂多糖（lipopolysaccharide，LPS），探究LPS对C2C12的最佳致炎浓度和作用时间，复制体外骨骼肌炎症细胞最佳模型；探究消炎止痛膏和双氯芬酸钠对C2C12肌管炎症模型的最佳干预浓度。采用CCK-8测定细胞活性，ELISA检测加入消炎止痛膏后LPS诱导的C2C12中IL-1β和IL-6浓度，SOD和MDA含量。   结果   ①分化实验：经2%马血清诱导，C2C12第4~5 d分化明显，肌管形成，第9~10 d达高峰。②C2C12炎症模型：在1 μg/mL LPS作用24 h后C2C12炎症反应最明显，且CCK-8显示细胞活性无明显改变。③药物浓度：消炎止痛膏溶液1.25 mg/mL、双氯芬酸钠溶液6.25 μg/mL作用24 h下C2C12炎症反应最轻，且CCK-8显示细胞活性无明显改变。④机制：与模型组比较，1.25 mg/mL消炎止痛膏显著抑制LPS诱导的C2C12肌管细胞IL-1β（P=0.006）和MDA水平（P=0.002），提高SOD水平（P=0.0001）；与双氯芬酸钠组比较，1.25 mg/mL消炎止痛膏抑制LPS诱导的C2C12肌管细胞IL-1β水平无显著性差异（P=0.188），但提高SOD（P=0.0001）和抑制MDA水平（P=0.014）有显著性差异。  结论   消炎止痛膏成分可降低LPS诱导的C2C12肌管炎症模型IL-1β、IL-6和MDA水平，提高SOD水平，可能与减轻组织炎症反应、降低机体氧化应激损害有关。

Objective To study the effect mechanism of Xiaoyanzhitong ointment on lipopolysaccharide-induced C2C12 myofibers.    Methods    C2C12 skeletal muscle cells were cultured in vitro and differentiated into mature muscle tubes with 2% horse serum. The blank group, model group, diclofenac sodium group and Xiaoyanzhitong group were set. LPS was added on the non-blank groups to explore the optimal inflammatory concentration and duration of LPS on C2C12, and to replicate the optimal inflammatory cell model of skeletal muscle in vitro, thus to explore the optimal intervention concentration of Xiaoyanzhitong ointment and diclofenac sodium on C2C12 cell inflammation model. Cell activity was detected by CCK-8 method. The concentrations of IL-1β and IL-6, SOD and MDA content in LPS treated C2C12 cells were detected by ELISA after the addition of Xiaoyanzhitong ointment.    Results   ① The results of differentiation experiment showed that C2C12 differentiation was obvious on the 4th~5th day. ② C2C12 inflammatory model results showed that the inflammatory reaction of C2C12 cells was the most obvious after 24h treatment with 1 μg/ml LPS, and CCK-8 result showed there was no significant change in cell activity. ③ The results of drug concentration exploration showed that the inflammatory reaction of C2C12 was the lightest under the treatment of 1.25 mg/ml Xiaoyanpain-relieving ointment solution and 6.25 μg/ml diclofenac sodium solution for 24 h, and CCK-8 result showed no significant change in cell activity. ④ Compared with model group, 1.25 mg/ml Xiaoyanzhitong ointment significantly inhibited IL-1β level and MDA level, and increased SOD level in LPS-induced C2C12. Compared with diclofenac sodium group,  There was no significant difference of 1.25 mg/ml Xiaoyanzhitong ointment in the inhibition of IL-1β level in LPS-induced C2C12 cells (P=0.188), but there were significant differences in the enhancement of SOD level (P=0.0001) and inhibition of MDA level (P=0.014).    Conclusions    The composition of Xiaoyanzhitong ointment can reduce the levels of IL-1β, IL-6 and MDA in C2C12 cells under LPS administration, and increase the level of SOD, which may be related to the reduction of tissue inflammation and the alleviation of oxidative stress damage.