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目的 探讨对氨基水杨酸钠(PAS-Na)对铅诱导PC12细胞凋亡的影响.方法 PC12细胞培养至其对数生长期后,正常对照组和正常+PAS-Na 500μmol·L-1组细胞于正常培养液中培养24 h后弃培养液,前者加入正常培养液、后者加入PAS-Na继续培养24 h.醋酸铅模型组及醋酸铅+PAS-Na 20,100和500μmol·L-1组先与醋酸铅(终浓度10μmol·L-1)共培养24 h后弃培养液,再加入相应浓度PAS-Na继续培养24 h.用MTT法测定细胞存活率,试剂盒方法测定细胞内还原型谷胱甘肽(GSH)含量,Hoechst33342荧光染色检测凋亡率,AnnexinⅤ/PI双染流式细胞术检测PC12细胞早期凋亡率,Western蛋白质印迹法检测Bcl-2、Bax和P53蛋白水平.结果 与正常对照组比较,醋酸铅模型组细胞存活率降低(P<0.05),细胞凋亡形态变化典型,细胞早期凋亡率增高(P<0.05),细胞内GSH含量降低(P<0.01),P53蛋白水平升高(P<0.01),Bax/Bcl-2比值升高(P<0.01);正常+PAS-Na 500μmol·L-1组上述指标未见明显变化.与醋酸铅模型组比较,醋酸铅+PAS-Na组细胞存活率增高(P<0.05),细胞凋亡率和早期凋亡率均降低(P<0.05),细胞内GSH含量增高(P<0.01),P53蛋白水平和Bax/Bcl-2比值降低(P<0.05).结论 PAS-Na对铅致PC12细胞凋亡有一定的拮抗作用,其机制可能与PAS-Na抗脂质过氧化损伤和降低Bax/Bcl-2比值有关.“,”OBJECTIVE To explore the effects of sodium para-aminosalicylate acid (PAS-Na) on apoptosis of PC12 cells induced by lead-exposure. METHODS PC12 cells were cultured to their logarithmic growth phase before cells in normal control group and normal+PAS-Na 500μmol · L-1 group were with normal medium for 24 h. The former were cultured with the normal medium, and the latter with 500μmol·L-1 PAS-Na medium for another 24 h. Lead acetate model group and lead acetate+PAS-Na 20, 100, 500μmol·L-1 intervention groups were incubated with medium containing lead acetate (the final concen?tration of 10 μmol · L-1 ) for 24 h, and were added with a corresponding concentration of PAS-Na for another 24 h after the culture solution was removed. Subsequently, MTT assay was used to observe the viability of PC12 cells, whereas intracellular glutathione (GSH) content was estimated by assay kit. Apop?tosis of PC12 was detected by Hoechst33342 fluorescence staining and AnnexinⅤ/PI double staining flow cytometry. Western blotting was performed to detect levels of Bcl-2, Bax and P53 proteins. RESULTS Compared with the normal control group, the survival rate of cells and the content of intracellular GSH decreased in Pb model group (P<0.05). Typical morphological characteristics were found by Hoch?est33342 staining, and apoptosis rate increased (P<0.05). Western blotting showed that the level of Bcl-2 protein decreased, while levels of Bax and p53 protein increased, and the Bax/Bcl-2 ratio increased signifi?cantly in lead acetate group (P<0.05). In normal+PAS-Na 500μmol·L-1 group, the above indexes did not change significantly. Compared with the lead acetate group, the survival rate of PC12 cells and intracel?lular GSH content were increased in lead acetate+PAS-Na intervention group (P<0.05), while the Bax/Bcl-2 ratio and level of p53 protein were decreased (P<0.05). CONCLUSION Intervention with PAS-Na can protect PC12 cells from apoptosis induced by lead exposure, which may be related to anti-lipid peroxidation damage and decrease in the Bax/Bcl-2 ratio.