NF-κB在不同程度铅暴露大鼠胎盘中的表达研究

The effects of lead exposure on placental NF-κB expression

目的探讨孕期不同阶段铅暴露对大鼠胎盘核转录因子NF-κB(nuclear ranscription factor-κB,NF-κB)表达的影响,推测铅暴露对胎盘的损伤机制。方法108只大鼠随机分为A,B,C,D4组,0.025%醋酸铅对实验组大鼠染毒。根据大鼠孕期3周推算,足月剖宫产,孕末期腹腔静脉取血,采用原子吸收光谱仪测定孕期不同阶段低水平铅暴露后的大鼠血铅水平。统计记录各组的平均血铅水平。免疫组织化学方法测定大鼠胎盘内NF-κB的表达。结果实验组大鼠孕末期血铅水平均高于对照组(P<0.01)。受孕大鼠血铅水平与胎盘重量呈负相关(r=-0.652、P<0.01)。孕期染铅组其胎盘NF-κB表达量高于对照组,各组比较除了B组和C以外差别都具有显著性(P<0.01)。结论孕期不同阶段的铅暴露对NF-κB的活化产生不同的影响,其对胞浆细胞器的损害可能干扰母体与胎儿之间营养物质和氧气的交换,这可能是导致异常妊娠的原因之一。

Objective：To investigate the toxicity of lead exposure on the placenta at different dosages and the relationship with placental expression of NF-κB. Methods：108 Wistar rats were randomly divided into four groups （A,B,C,D）for consumption of water with or without 0.025% lead acetate during various gestationalperiods;Blood lead content was determined by atomic absorption spectrophotometry. Placental NF-κB expression was evaluated by immunohistochemistry. Results：Maternal blood lead levels in the rats was significantly higher compared to controls（P〈0.01）. Maternal blood lead levels in the rats negatively correlated with placental weight（r=-0.652,P〈0.01）. On the other hand,placental expression of NF-κB in lead-exposed rats was significantly higher than that in controls（P〈0.01）. Conclusion：Lead exposure at various gestational periods produce varied effects,with NF-κB activation following lead exposure.Injury to cytoplasmic organelles may interfere with the nutrition and oxygen exchange between mother and fetus,which may be contribute to abnormal pregnancy outcomes.