发育期不同年龄段铅中毒幼鼠模型制备

Establishment of lead-exposed rat models at different developmental stages

目的建立发育期不同年龄段中重度铅中毒幼鼠模型,为后续探讨驱铅治疗奠定模型基础。方法 18只20日龄幼鼠随机分为3组:对照组、高铅组(0.2%醋酸铅溶液)及低铅组(0.05%醋酸铅溶液),构建儿童期铅中毒模型;同样方法构建青春期(18只40日龄幼鼠)铅中毒模型。检测血铅、胫骨密质骨骨铅及松质骨骨铅,确定铅中毒水平。结果两年龄段对照组与染毒组血铅差异有统计学意义(P<0.01),两年龄段高铅组血铅明显高于低铅组血铅(P<0.01),无论是高铅组还是低铅组,儿童期血铅水平均高于青春期(P<0.01)。儿童期与青春期无论是密质骨骨铅还是松质骨骨铅,染毒组与对照组间差异均存在统计学意义(P<0.01)。儿童期骨铅水平较青春期高,密质骨骨铅水平间差异有统计学意义(P<0.01),而松质骨骨铅水平差异无统计学意义(P=0.245)。分别做血铅和密质骨骨铅及松质骨骨铅间的相关分析,血铅和密质骨骨铅/松质骨骨铅间显著相关(密质骨骨铅:r=0.931,P=0.000;松质骨骨铅:r=0.918,P=0.000)。结论建立不同年龄段相同血铅或骨铅水平的幼鼠模型,需给予不同的铅暴露水平。

Objective To establish the rat models of developmental lead exposure at different age groups and offer a footstone for the follow-up studies.Methods Two kinds of animal models of developmental lead exposure were established：the model lead-exposed during childhood（20 to 40 days old） and the model lead-exposed during adolescence （40 to 60 days old）.Eighteen Sprague-Dawley rats were randomly divided into control,low lead-exposed（treated by 0.05% lead acetate in their drinking water for 20 days） and high lead-exposed（treated by 0.2% lead acetate in their drinking water for 20 days） group in both models,6 in each group.The blood lead levels and bone lead levels（lead levels in cancellous bone and compact bone were respectively measured） were measured to evaluate lead poisoning levels in rats.Results The blood lead levels and bone lead levels of lead exposure groups in both childhood and adolescence models were significantly higher than those of control groups（P〈0.01）.What＇s more,in both models,the blood lead levels of high lead-exposed groups were significantly higher than those of low lead-exposed groups（P〈0.01）.In lead exposure groups,the blood lead levels and lead levels in compact bone of rats in childhood model were higher than those in adolescence model（P〈0.01）.But,lead levels in cancellous bone had no significant differences（P=0.245）.In each group,the blood lead levels and bone lead levels were highly correlated（compact bone：r=0.931,P=0.000;cancellous bone：r=0.918,P =0.000）.Conclusion Different levels of lead exposure are needed to establish rat models with same blood or bone lead levels among different age groups.