丰富环境对锰中毒小鼠的干预作用及机制探讨

发布时间：2018-05-07 22:06

本文选题：锰中毒 + CREB　；参考：《广西医科大学》2013年硕士论文

【摘要】：目的：观察丰富环境和贫瘠环境干预对锰中毒小鼠学习记忆能力和神经发生的影响,并初步探讨其作用机制,为锰中毒的防治提供理论基础和实验依据。方法：选用清洁级成年昆明小鼠雌性40只,体重20±2g,随机分成空白对照组(CG)、正常环境染锰组(SEG)、丰富环境干预染锰组(EEG)以及贫瘠环境干预染锰组(IEG),共4组,每组10只。采用腹腔注射氯化锰(MnCl220mg/kg)的方式制造小鼠锰中毒模型,进行染毒3周,而对照组腹腔注射同等剂量的生理盐水,同时各组小鼠在相应的环境中进行刺激。用Morris水迷宫的方法检测各组小鼠的学习记忆能力,用免疫荧光化学法检测小鼠SVZ和SGZ内DCX的表达,用免疫组织化学的方法检测海马内CREB蛋白的表达。用Image-Pro Plus6.0图像分析系统计算SVZ和SGZ内DCX的阳性表达的平均光密度值及海马区CREB阳性表达的平均光密度值,用SPSS软件对所有数据做统计分析,并作线性相关分析。结果：1.水迷宫定位航行试验中正常环境染锰组小鼠的逃避潜伏期比空白对照组小鼠的明显延长(p0.05),而丰富环境干预染锰组小鼠的逃避潜伏期明显比正常环境干预染锰组小鼠的缩短(p0.05),贫瘠环境干预染锰组与正常环境干预染锰组之间无统计学差异；空间探索实验中,正常环境染锰组小鼠穿越平台的次数比空白对照组少,丰富环境干预染锰组穿越平台的次数则比正常环境染锰组多,贫瘠环境干预染锰组比正常环境染锰组少,差异有统计学意义(p0.05)。2.DCX免疫组织化学检测结果显示,正常环境干预染锰组和贫瘠环境干预染锰组SVZ和SGZ区DCX阳性荧光强度明显比对照组弱；丰富环境干预染锰组SVZ和SGZ区DCX阳性荧光强度明显比正常环境染锰组强,差异有统计学意义,与对照组比较无统计学差异。3.CREB免疫组织化学检测结果显示,正常环境染锰组和贫瘠环境干预染锰组海马CA1区CREB蛋白表达量明显低于对照组(p0.01)；丰富环境干预染锰组海马CA1区内CREB蛋白表达量比正常环境干预染锰组的要明显增多(p0.01),与对照组无统计学差异。4.线性相关分析表明,CREB的表达与小鼠记忆能力及SGZ内DCX的表达呈正相关。结论：1.丰富环境干预可改善锰中毒小鼠的学习记忆能力。2.丰富环境干预可促进锰中毒小鼠脑内的神经发生。3.丰富环境干预可增加海马内CREB的表达。4.贫瘠环境干预降低锰中毒小鼠的学习记忆能力,抑制了脑内的神经发生,降低了锰中毒小鼠的海马内的CREB的表达。5.丰富环境干预改善锰中毒小鼠学习记忆能力促进脑内神经发生的机制,可能与丰富环境干预增加海马内CREB的表达有关。
[Abstract]:Objective: to observe the effects of rich and barren environment intervention on learning and memory ability and neurogenesis in mice with manganese poisoning, and to explore its mechanism, and to provide theoretical basis and experimental basis for prevention and treatment of manganese poisoning. Methods: forty adult Kunming mice of clean grade, weighing 20 卤2 g, were randomly divided into 4 groups: control group (10 rats), normal environment exposed group (EEGG), enriched environment group (EEGG) and barren environment group (10 rats in each group). The mice model of manganese poisoning was made by intraperitoneal injection of MnCl _ 220mg / kg. The mice in the control group were injected with the same dose of normal saline for 3 weeks, and the mice in each group were stimulated in the corresponding environment. The ability of learning and memory was detected by Morris water maze method, the expression of DCX in SVZ and SGZ was detected by immunofluorescence method, and the expression of CREB protein in hippocampus was detected by immunohistochemical method. The average optical density of DCX positive expression in SVZ and SGZ and the average optical density of CREB positive expression in hippocampus were calculated by Image-Pro Plus6.0 image analysis system. All the data were statistically analyzed by SPSS software and linear correlation analysis was made. The result is 1: 1. In the water maze navigation test, the escape latency of the mice exposed to manganese in the normal environment was significantly longer than that of the control group, while the escape latency of the mice in the enriched environment group was significantly smaller than that in the control group. There was no significant difference between the barren environmental intervention group and the normal environmental intervention group. In the space exploration experiment, the mice in the normal environment exposed to manganese had less times of crossing the platform than those in the blank control group, and the rich environment intervention group had more times of crossing the platform than that of the normal environment group. The poor environment intervention group was less than that in the normal environment group, and the difference was statistically significant (P 0.05). 2. The results of DCX immunohistochemical analysis showed that there was no significant difference between the two groups. The positive fluorescence intensity of DCX in the SVZ and SGZ regions in the normal and barren environment groups was significantly weaker than that in the control group, and the positive fluorescence intensity of DCX in the SVZ and SGZ regions in the rich environment group was significantly stronger than that in the normal environment group. The difference was statistically significant. There was no significant difference between the two groups. 3. The results of CREB immunohistochemistry showed that, The expression of CREB protein in the CA1 region of hippocampus in the manganese exposed group and the barren environment group was significantly lower than that in the control group, while the CREB protein expression in the CA1 region in the rich environment group was significantly higher than that in the control group. There was no significant difference between the control group and the control group. Linear correlation analysis showed that the expression of CREB was positively correlated with the memory ability of mice and the expression of DCX in SGZ. Conclusion 1. Rich environment intervention can improve the learning and memory ability of mice exposed to manganese. 2. 2. Rich environment intervention can promote neurogenesis. 3. 3 in the brain of mice with manganese poisoning. Rich environment intervention increased the expression of CREB. 4. 4. The barren environment intervention decreased the learning and memory ability, inhibited the neurogenesis in the brain and decreased the expression of CREB in hippocampus of the mice exposed to manganese. The mechanism of rich environment intervention to improve the learning and memory ability of mice induced by manganese poisoning may be related to the increase of CREB expression in hippocampus.
【学位授予单位】：广西医科大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：R114

【参考文献】