染铅大鼠铁过载致神经元损伤特殊染色法分析

目的探讨长期铅暴露大鼠铁过载对神经元的损伤。方法SD大鼠母代与子代分别设对照、低、高剂量铅暴露组（母代：800、1 500 mg/L，子代：300、900 mg/L 乙酸铅饮水方式染毒）连续70周；电感耦合等离子体发射光谱仪（ICP-AES）测血液和海马元素铅及铁，同部位海马石蜡切片分别行铁染色及硫堇染色并进行图片融合。结果染铅后，大鼠血和海马铅及海马铁含量均增加（P<0.01）；低、高剂量铅暴露组子代大鼠海马CA3区铁沉积IOD值分别为（5 930.71±2 517.68）和（1 1382.43±2 551.14），均高于对照组的（3 786.78±1 256.37），差异有统计学意义（P<0.01）；低、高剂量铅暴露组子代大鼠海马CA1区的神经元数量分别为（70.71±11.80）、（70.37±17.53）个/视野，均低于对照组的（83.71±12.60）个/视野，差异有统计学意义（P<0.01）；图像融合显示，染铅大鼠神经元内铁沉积增加而神经元数量及层数减少，损伤加重。结论基于铁染色和硫堇染色图像融合可直观地观察铅暴露大鼠铁过载部位神经元损伤。

Quantitative analysis of neuron damage caused by iron overload in lead exposure rats with special staining image method

ObjectiveTo explore neuron damage caused by iron overlosd in longterm lead(Pb) exposure rats.MethodsSprague-Dawley maternal and pup rats were randomly divided into control groups(without lead exposure),low exposure groups(with 800 and 300 mg/L lead acetate in drinking warter for maternal and pup rats),and high expoure groups(with 1500 and 900 mg/L lead acetate in drinking water for maternal and pup rats).The treatments lasted for 70 weeks.The contents of Pb and iron in blood and brain were determined with inductively coupled plasma atomic emission spectrometry (ICP-AES).Two adjacent hippocampus paraffin slices(3 μm apart from each other) were stained with ferric iron and thionine,then the images were merged.ResultsThe lead concentrations in blood and brain and Fe levels of hippocampus were significantly higher(P<0.01) after the exposure of lead.The intergrated optical density(IOD) for Perl's staining of CA3 of low and high lead exposure groups of were 5 930.71±2 517.6 and 11 382.43±2 551.14,and significantly higher than that of the control (3 786.78± 1 256.37) (P<0.01).The numbers of neurons in CA1 of low and high lead-exposure group were 70.71±11.80 cells/view and 70.37±17.53 and significantly lower than that of the control (83.71±12.60) (P<0.05).Image mergence by IPP6.0 indicated that the number and layer of the neurons were decreased and the injuries of the neurons were aggravated.ConclusionImage mergence of Perl's and thionine staining can intuitively be used for quantitative analysis of neuron damage caused by iron overload.