澄海和濠江区新生儿脐带血镉和吸烟对胎盘金属硫蛋白mRNA表达量和胎龄的影响

目的:探讨澄海和濠江区的镉(Cd)暴露对胎盘金属硫蛋白(MT)mRNA表达量和胎龄的影响。方法:石墨炉原子吸收光谱仪检测澄海和濠江区85名新生儿胎盘中Cd浓度;用RT-PCR检测MTmRNA的相对表达量,以及相关影响因素问卷的调查。结果:澄海区新生儿脐带血Cd(2.0±0.7)μg/L;濠江区(2.5±0.5)μg/L;澄海区MTmRNA表达量中位数为0.116(25%～75%区间为0.081～0.219),濠江区0.143(25%～75%区间为0.080～0.252);濠江区丈夫吸烟、Cd暴露情况与胎盘中MT表达量呈正相关,与胎龄负相关。结论:被动吸烟以及Cd暴露都会诱导MTmRNA的表达,Cd暴露也会导致胎龄缩短。

Cadmium Exposure in Umbilical Cord Blood and Influence of Smoking on Alternated Expression of Placental Metallothionein mRNA and Gestational Age in Chenghai and Haojiang Districts

Objective:To investigate the alternated metallothionein(MT)mRNA expression in placenta and gestational age of neonates correlated to cadmium(Cd)exposure in umbilical cord blood.Methods:Levels of Cd were determined by graphite furnace atomic absorption spectrometry in 41 umbilical cord blood samples from Chenghai district and 44 from Haojiang.MT mRNA expression was tested by RT-PCR.The self-designed questionnaires were administered.Results:The mean umbilical cord blood Cd level was(2.0±0.7)μg/L in Chenghai and(2.5±0.5)μg/L in Haojiang.The median mRNA expression level was 0.116(25% ～ 75%:0.081 ～ 0.219)in Chenghai and 0.116(25% ～ 75%:0.081 ～ 0.219)in Haojiang.The umbilical cord blood Cd level was negatively correlated with gestational age of neonate.The placental Cd level was negatively correlated with birth weight of neonate.There was a positive correlation between Cd and MT mRNA expression level.Conclusion:MT mRNA expression is induced and the gestational age is decreased,which suggested that Cd in umbilical cord blood and passively smoking would affect the MT in placenta and shorten the gestational age in Haojiang district.