AMPA受体在亚慢性染铝致大鼠学习记忆损伤中的作用

发布时间：2018-04-21 06:45

本文选题：铝 + AMPA受体　；参考：《山西医科大学》2013年硕士论文

【摘要】：[目的]通过对大鼠亚慢性染铝,建立学习记忆损伤模型,观察AMPA受体在铝致大鼠学习记忆损伤中的可能作用。 [方法] 1、建立动物染铝模型：健康雄性刚成年SD大鼠36只,按体重随机分为：0.41mg/kg-bw、0.82mg/kg·bw、1.23mg/kg-bw麦芽酚铝[Al(mal)3]组和对照组(生理盐水),腹腔注射染毒8周。 2、采用石墨炉原子吸收分光光度法测定大鼠脑中铝含量。 3、采用Morris水迷宫试验进行大鼠学习记忆能力检测,其中定位导航试验检测大鼠空间学习能力,空间探索实验检测大鼠的空间记忆能力。 4、采用HE染色法观察大鼠海马区病理组织学变化。 5、采用实时荧光定量PCR法检测AMPA受体各亚单位GluRl,GluR2,GluR3基因表达情况。 6、采用免疫组化和Western blot法检测大鼠脑组织中AMPA受体亚单位GluR1, GluR2, GluR3的蛋白表达水平。 [结果] 1、随着染铝剂量的增加,染铝组大鼠脑铝含量也逐渐增加,并且其余各组与对照组相比,差别有统计学意义(P0.05)。 2、大鼠学习记忆能力测试结果表明与对照组相比,中、高剂量组大鼠找到平台时间明显延长(P0.05,P0.05)。中、高剂量组在目标象限停留时间与对照组相比都明显减少(P0.05,P0.05),高剂量组穿越平台次数与对照组相比明显减少(P0.05)。 3、HE染色结果表明随着铝剂量的增加,大鼠海马组织锥体层细胞排列分散,细胞数目减少,出现核固缩、空泡变性等病理改变。 4、实时荧光定量PCR法结果表明随着染铝剂量的增加,大鼠海马内的AMrA受体各亚基GluRl,GluR2,GluR3基因表达下降,低、中、高剂量组的基因表达较对照组均显著降低(P0.01,P0.01,P0.05)。 5、免疫组化法结果发现不同剂量组大鼠海马区可见不同程度的棕黄色深染颗粒(阳性表达),并且随着染铝剂量的增加,阳性表达越来越少。G1uRl低、中、高剂量组与对照组相比表达下降(P0.01)；G1uR2的低、中、高剂量组与对照组相比,阳性表达也逐渐下降(P0.01)；G1uR3蛋白表达也有所下降,但各染铝剂量组与对照组相比没有统计学意义。Westem b10t法结果表明AMPA受体各亚基蛋白水平随着染铝剂量的增加而呈逐渐下降趋势。GluRl的中、高剂量组蛋白表达较对照组均显著降低(P0.01)；G1uR2的蛋白表达呈下降趋势,高剂量组的蛋白表达较对照组显著降低(P0.01)；G1uR3蛋白表达呈下降趋势,但各染铝剂量组与对照组相比没有统计学意义。 [结论] 亚慢性染铝后,大鼠脑内铝含量表达升高,学习记忆能力下降,脑内海马区细胞形态发生变化。在此过程中,也观察到海马AMPA受体亚单位在基因和蛋白水平表达下降,提示AMPA受体表达下降可能是铝致大鼠学习记忆损伤的作用机制之一。
[Abstract]:[Objective] to establish a learning and memory impairment model by subchronic aluminum exposure in rats and observe the possible role of AMPA receptor in learning and memory impairment induced by aluminum.
[method]
1, an animal model of aluminum dye was established: 36 healthy male adult SD rats were randomly divided into 0.41mg/kg-bw, 0.82mg/kg / BW, 1.23mg/kg-bw maltol aluminum [Al (mal) 3] group and control group (physiological saline) and intraperitoneal injection for 8 weeks.
2, the content of aluminum in rat brain was determined by graphite furnace atomic absorption spectrometry.
3, the Morris water maze test was used to test the learning and memory ability of rats, in which the spatial learning ability of rats was detected by positioning navigation test, and spatial memory ability of rats was detected by space exploration experiment.
4, HE staining was used to observe histopathological changes in the hippocampus of rats.
5, real-time fluorescence quantitative PCR was used to detect the expression of AMPA receptor subunits GluRl, GluR2 and GluR3 genes.
6, immunohistochemistry and Western blot were used to detect the protein expression level of AMPA receptor subunit GluR1, GluR2 and GluR3 in rat brain.
[results]
1, as the dose of aluminum increased, the aluminum content in the brain of the rats exposed to aluminum increased gradually, and there was a significant difference between the other groups and the control group (P0.05).
2, the test results of learning and memory ability of rats showed that compared with the control group, the time of finding the platform in the high dose group was significantly longer (P0.05, P0.05). In the high dose group, the stay time in the target quadrant was significantly reduced (P0.05, P0.05), and the number of high dose group crossing platform decreased significantly compared with the control group (P0.05).
3, the results of HE staining showed that with the increase of aluminum dose, the pyramidal cells in the hippocampus of the rat were arranged and dispersed, the number of cells decreased, and the nuclear pyknosis, vacuolation and other pathological changes appeared.
4, the results of real time fluorescence quantitative PCR showed that the expression of GluRl, GluR2, GluR3 gene of AMrA receptor in hippocampus of rats decreased with the increase of dose of aluminum dye, and the expression of gene expression in high dose group decreased significantly (P0.01, P0.01, P0.05) in the high dose group.
5, the results of immunohistochemical staining found that the hippocampus of the rats in different doses was found to have different degrees of brown and yellow deep stained particles (positive expression), and with the increase of the dose of aluminum, the positive expression was less and less.G1uRl, the high dose group was lower than the control group (P0.01), and the low, middle and high dose group of G1uR2 was positive expression compared with the control group. It also decreased (P0.01), and the expression of G1uR3 protein decreased, but there was no statistical significance between the dosage group and the control group..Westem b10t method showed that the level of AMPA receptor subunit protein decreased gradually in.GluRl with the increase of aluminum dose, and the expression of high dose histone was significantly lower than that of the control group (P0.01). The protein expression of G1uR2 decreased significantly, the expression of protein in high dose group was significantly lower than that in the control group (P0.01), and the expression of G1uR3 protein showed a declining trend, but there was no statistical significance in the dosage group of all aluminum dyes compared with the control group.
[Conclusion]
After subchronic aluminum staining, the expression of aluminum content in the brain of rats increased, the ability of learning and memory decreased and the cell morphology of the hippocampus in the brain changed. In this process, the expression of AMPA receptor subunit in the hippocampus decreased at the level of gene and protein, suggesting that the decline of AMPA receptor expression may be one of the mechanisms of learning and memory impairment in rats.

【学位授予单位】：山西医科大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：R114

【参考文献】