Pregnancy At Different Stages Of Lead Exposure On Rat Placental Thrombosis Regulatory Protein Nuclear Factor-¦Êb In The Experimental Study,

Objective To investigate the toxicity of lead exposure on the placenta at different dosages and the relationship with placental expression of NF-κB and thrombomodulin.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 gestational periods; Blood lead content was determined by atomic absorption spectrophotometry. Placental NF-κB and thrombomodulin expression was evaluated by immunohistochemistry. TM mRNA was evaluated by fluorescent quantitative real time PCR.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). The placental expression of TM mRNA in lead-exposed rats was corresponding with the expression of TM protein. The tendency was increased continuous in group B, group C and group D. The TM expression in group B and group C was lower than in group A, whereas the expression in group D was higher than in group A (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. On the other hand, Lead exposure on rat placental may affect the expression of thrombomodulin. This effect could be associated with impairment in the placenta and may represent one mechanism by which prenatal lead exposure, caseuse impairment by consumptive intravascular coagulation and placental vascularization.