妊娠大鼠低铅暴露对子代海马GFAP表达影响

Effects of prenatal exposure to low level lead on hippocampal GFAP expression of rats' offspring

目的观察母体孕期低水平铅暴露对子代大鼠海马组织胶质原纤维酸性蛋白(GFAP)和mRNA表达的影响,探讨铅影响学习记忆的分子机制。方法孕鼠随机分为4组,自怀孕1d起分别给予蒸馏水、125,250,500mg/L醋酸铅饮水,直到仔鼠出生。分别在仔鼠出生后1,21,60d,采用免疫组化和原位杂交方法观察海马CA1区GFAP蛋白和mRNA表达的变化。结果各染铅组仔鼠1,21d时海马CA1区GFAP蛋白和mRNA阳性细胞数显著高于对照组(P<0.05),而60d时未见明显差异。结论妊娠期母体低水平铅暴露可以使仔鼠海马CA1区GFAP蛋白和mRNA表达增加,这可能是铅影响学习记忆的分子机制之一。

Objective To observe the effects of prenatal exposure to low level lead on the protein and mRNA expression of glial fibrillary acidic protein （GFAP） in hippocampus of rat＇s offspring, and to explore the molecular mechanisms of lead on learning and memory. Methods The pregnant rats were randomizedly divided into 4 groups and provided with doubly evaporated water in control groups and 125,250,500 mg/L lead acetate solution via drinking water in treatment groups respectively during pregnancy. The GFAP protein and mRNA expression at hippocampal CA1 region were observed by immunohistochemistry and in situ hybridization. Results The cell numbers of GFAP protein and mRNA positive expression at 1-day and 21-day old offsprings in treatment group were significantly higher than that of control（ P 〈 0.05 ）, but no significant difference at 60-day old offsprings. Conclusion Prenatal exposure to low level lead could promote the GFAP protein and mRNA expression at hippocampal CA1 region, which maybe is one of the molecular mechanisms of lead on learning and memory.