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目的:探讨芍药苷对醋酸铅诱导海马神经元凋亡的影响及潜在机制。方法:于2020年9月，从胎鼠中分离培养原代海马神经元细胞，并利用细胞免疫荧光法进行鉴定。MTT法测定细胞活力确定醋酸铅诱导海马神经元凋亡浓度及时间，芍药苷细胞毒性研究评价芍药苷浓度及其对醋酸铅诱导海马神经元凋亡的影响。依据结果选取不同浓度芍药苷干预海马神经元细胞，作用24 h后，加醋酸铅染毒，同时设空白组和模型组，测定海马神经元细胞中活性氧（ROS）、超氧化物歧化酶（SOD）、乳酸脱氢酶（LDH）、丙二醛（MDA）及半胱氨酸天冬氨酸蛋白酶-3 （Caspase-3）含量；蛋白免疫印迹（Western blotting）检测海马神经元细胞中细胞外信号调节激酶（ERK）、磷酸化ERK (p-ERK）、p38丝裂原活化蛋白激酶（MAPK）、磷酸化p38 MAPK (p-p38MAPK）、c-Jun氨基端激酶（JNK）、磷酸化JNK (p-JNK）蛋白表达。结果:分离培养的海马神经元细胞经免疫荧光化学染色鉴定后，给予醋酸铅处理，MTT结果显示醋酸铅浓度25 μmol/L，处理24 h毒性效果最佳。80 μmol/L以下浓度芍药苷对海马神经元细胞均无细胞毒性作用；与模型组比较，20、40、80 μmol/L芍药苷干预组海马神经元细胞活力均明显升高（n P<0.05）。与空白组比较，模型组海马神经元细胞中ROS活力、LDH释放水平、MDA和Caspase-3含量均明显升高（n P<0.01），SOD活力明显降低（n P<0.01）；与模型组比较，40、80 μmol/L芍药苷干预组海马神经元细胞中ROS活力、LDH释放水平、MDA和Caspase-3含量明显降低（n P<0.05），SOD活力明显升高（n P<0.05）。与模型组比较，40、80 μmol/L芍药苷干预组海马神经元细胞中p-ERK/ERK比值明显升高（n P <0.01），p-p38MAPK/p38MAPK和p-JNK/JNK比值明显降低（ n P<0.05）。n 结论:芍药苷可能通过MAPK信号通路，下调p-p38MAPK、p-JNK蛋白表达，上调p-ERK蛋白表达，抑制醋酸铅诱导的大鼠海马神经元凋亡。“,”Objective:To investigate the effect and underlying mechanism of paeoniflorin on hippocampal neuron apoptosis induced by lead acetate.Methods:In September 2020, primary hippocampal neuronal cells were isolated and cultured from fetal rats, and identified using cellular immunofluorescent. MTT assay was used to measure the cell viability to determine the concentration and time of lead acetate-induced hippocampal neuron apoptosis. MTT was also used to evaluate the effect of paeoniflorin concentration on the apoptosis of hippocampal neurons induced by lead acetate. According to the results, different concentrations of paeoniflorin were selected to intervene hippocampal neuron cells, after 24 h, lead acetate was added to the cells, meanwhile, blank and model groups were set up, the content of reactive oxygen species (ROS) , superoxide dismutase (SOD) , lactate dehydrogenase (LDH) , malondialdehyde (MDA) and Caspase-3 were measured. Extracellular signal regulated kinase (ERK) , phosphorylated ERK (p-ERK) , p38 mitogenn -activated protein kinases (p38MAPK) , phosphorylated p38MAPK (p-p38MAPK) , c-Jun N-terminal kinase (JNK) and phosphorylated JNK (p-JNK) protein expression in hippocampal neuronal cells were determined by Western blotting.n Results:The isolated and cultured hippocampal neurons were identified by immunofluorescence chemical staining and then treated with lead acetate, MTT results showed that lead acetate had the best toxicity effect when treated for 24 h at a concentration of 25 μmol/L. Paeoniflorin showed no cytotoxic effect on hippocampal neuronal cells when the concentrations below 80 μmol/L. Compared with the model group, the activity of hippocampal neuronal cells was significantly increased after treating with 20, 40 or 80 μmol/L paeoniflorin ( n P<0.05) . Compared with the blank group, the ROS activity, LDH release level, MDA content and caspase-3 content were significantly increased (n P<0.01) , and the SOD activity was significantly decreased (n P< 0.01) in the hippocampal neuronal cells of the model group. Compared with the model group, the ROS activity, LDH release level, MDA content and caspase-3 content were obviously decreased (n P<0.05) , SOD activity was significantly increased (n P <0.01) after hippocampal neuronal cells were treated with 40 or 80 μmol/L paeoniflorin. Relative to the model group, the ratio of p-ERK/ERK were significantly up-regulated ( n P<0.01) , while the ratios of p-p38MAPK/p38MAPK and p-JNK/JNK were significantly down-regulated after hippocampal neuronal cells were treated with 40 or 80 μmol/L paeoniflorin (n P<0.05) .n Conclusion:Paeoniflorin may down-regulate the expression of p-p38MAPK and p-JNK protein, up-regulate the expression of p-ERK protein, and inhibit the apoptosis of hippocampal neurons induced by lead acetate through the MAPK signaling pathway.