铅暴露大鼠海马区神经颗粒素表达与学习记忆关系研究  

Relationship between neurogranin expression in hippocampus and learning-memory in lead-exposed rats

作　　者：马威[1] 吴艳霞[1] 吴文莉[1] 任易[1] 易艳东[1] 彭碧波[1] 朱琼洁[1] 宋宇[1] 

机构地区：[1]武汉市第一医院中心实验室,湖北武汉430022

出　　处：《中国儿童保健杂志》2010年第3期222-224,共3页Chinese Journal of Child Health Care

基　　金：武汉市卫生局项目(2007-43)

摘　　要：【目的】探讨铅接触大鼠脑组织海马区神经颗粒素表达及在学习记忆障碍中的作用。【方法】32只Wistar大鼠随机分为4组,每组8只,3个染铅组分别在饮用的蒸馏水中添加0.02%、0.10%、0.20%醋酸铅为低、中、高剂量染铅组,空白对照组饮用蒸馏水,连续45 d复制慢性铅中毒模型,对各组进行Morris水迷宫试验,麻醉后分别检测各组动物血铅、脑铅含量;RT-PCR检测海马区组织Ng mRNA、CaMKⅡmRNA表达;免疫组化方法检测P-CaMKⅡ表达,Western Blotting法检测Ng蛋白表达。【结果】1)与空白对照组比较,染铅各组血铅、脑铅含量均显著增高(P<0.01),高剂量组动物体重显著降低(P<0.05);2)Morris水迷宫结果显示,随染铅浓度增高,潜伏期显著延长(P<0.05);通过强化训练,各组动物均获得了一定的定位能力,但各染铅组动物潜伏期显著高于空白对照组(P<0.05);3)与空白对照组比较,各浓度染铅组Ng mRNA及CaMKⅡmRNA表达均显著降低(P<0.05);4)Ng的Western Blotting结果显示,与空白对照组比较,中、高剂量染铅组Ng蛋白表达均显著降低(P<0.01),低剂量组表达也下降,但没有显著差异;P-CaMKⅡ的免疫组化结果显示,与空白对照组比较,低、中、高剂量染铅组表达均显著降低(P<0.05或<0.01)。【结论】Ng作为突触后CaM结合蛋白和PKC的作用底物,参与介导了铅导致的的学习记忆障碍。[Objective] To study the expression of neurogranin in hippocampus of brain tissue in lead-exposed rats and its role in learning-memory disorder. [Methods] 32 Wistar rats were randomly divided into 4 groups. There were 8 rats in each group. Three lead-exposed groups were added 0. 02%,0. 10%, 0. 200% lead acetate in drinking distilled water respectively as low-, mid-, high-dose lead-exposed groups. Control group drank distilled water. Chronic lead-poisoning model was made in 45 consecutive days. Morris water maze test were performed in each group. Blood and brain lead concentrations were determined in each group after anesthesia. Ng mRNA and CaMK ]][ mRNA expression in hippocampus were determined by RT-PCR. p-CaMK ]] expression was determined by immunohistochemical assay. Ng protein expression was determined by Western blotting assay. [Results] 1）As compared with control group, blood and brain lead concentration were significantly increased in lead-exposed groups （P〈 0.01）. Body weights of high-dose group were significantly de- creased （P〈0.05）. 2）The results from Morris water maze showed that latent period was significantly prolonged along with the increasing of lead-exposed dose（P〈0.05）. By intensive training, certain location ability was obtained in rats of each group. But the latent periods of rats in each lead-exposed group were significantly higher than that in control group （P〈 0.05）. 3）As compared with control group, Ng mRNA and CaMK Ⅱ mRNA expressions in each lead-exposed group were significantly decreased （P〈0.05）. 4）The results from Ng protein by western blotting showed that, as compared with control group, Ng protein expressions in mid- and high-dose lead-exposed groups were significantly decreased（P〈0.01）. Ng protein expression was also decreased without significant differences. The results from Pp-CaMK Ⅱ immunohistochemical assay showed that, as compared with control group, its expressions in low-,mid- and high-dose lead-exposed groups were all significa

关 键 词：铅 铅中毒 神经颗粒素 钙离子偌调蛋白依赖性蛋白激酶Ⅱ 

分 类 号：R135.1[医药卫生—劳动卫生]