【摘要】 目的:通过检测微囊藻毒素-LR(MC-LR)对BV-2细胞内一氧化氮(NO)和一氧化氮合酶(NOS),以及培养上清液中的肿瘤坏死因子-α(TNF-α)和白介素-6(IL-6)表达的影响,为进一步探讨MC-LR引起中枢神经系统免疫反应奠定基础。方法:用MC-LR刺激BV-2细胞建立炎症模型,以四甲基噻唑蓝(MTT)法测定MC-LR对细胞的毒性作用;采用硝酸还原酶法检测BV-2细胞中NO的表达量;NOS分型法检测NOS的表达水平;酶联免疫吸附实验(ELISA)检测TNF-α和IL-6炎症因子的产生情况。结果:MC-LR染毒24h后,染毒浓度在0~128μg/L范围内,随着剂量的增加,细胞活性呈下降趋势(r=-0.609,P<0.05),其半数有效浓度(EC)为22.49 50μg/L。当染毒浓度≥5.0μg/L时,细胞分泌的IL-6和NOS的含量明显增加,与对照组比较差异具有统计学意义(P<0.05);10.0μg/L染毒后TNF-α和NO含量明显增加,与对照组比较差异具有统计学意义(P<0.05)。结论:MC-LR诱导BV-2细胞产生大量的炎性细胞因子NO、NOS、IL-6及TNF-α,引起神经系统的炎症反应。更多还原

【Abstract】 OBJECTIVE: To investigate the effects of mycrocystin-LR(MC-LR) on the neurotoxic mechanisms of the central nervous system,the contents of nitric oxide(NO),nitric oxide synthase(NOS),tumor necrosis factor-α(TNF-α),and interleukin- 6(IL-6) in BV-2 microglial cells were detected in our study. METHODS:With the methyl thiazolyl tetrazolium(MTT) assay,the cytotoxicity of the inflammatory model in BV-2 cells was performed after exposure to MC-LR. The levels of NO and NOS were measured by the nitric acid reductase assay and nitric oxide synthase assay,respectively. The contents of TNF-α and IL-6 were measured by enzyme-linked immunosorbent assay(ELISA). RESULTS:After exposure to MC-LR for 24 h,the viability in BV-2 cells was decreased with the increase of MC-LR concentration within the range of 0-28 μg/L(r=-0.609,P<0.05),and the median effective concentration(EC) was 22.49 50μg/L. Besides,the levels of IL-6 and NOS in BV-2 cells were increased at the concentration of 5-10 μg/L MC-LR,and the levels of TNF-α and NO were increased at the concentration of 10 μg/L MC-LR. Compared with control group,those differences above mentioned were statistically significant(P<0.05). CONCLUSION:MC-LR induced inflammatory response in BV-2 microglial cells by increases in p roduction o f NO,NOS,IL-6 and TNF-α.更多还原