甲醛对不同龄期大鼠认知功能影响及其分子机制研究

发布时间：2018-04-22 09:25

本文选题：甲醛 + 吸入染毒　；参考：《重庆医科大学》2007年硕士论文

【摘要】： 第一部分甲醛吸入染毒对不同龄期大鼠认知功能的影响目的:制作不同龄期大鼠甲醛吸入染毒模型,探讨甲醛吸入对不同龄期大鼠空间学习记忆能力的影响。方法:选择不同龄期的Wistar鼠36只,其中成年鼠(2-3月龄)、幼年鼠(生后20天)、新生鼠(生后1天)各12只,各年龄期大鼠随机分为对照组和染毒组,每组6只,雌雄不拘。染毒组大鼠置于60L有机玻璃染毒柜中,进行30天的连续染毒(甲醛浓度1mg/m3,2小时/天),对照组大鼠置于同规格的不含甲醛的有机玻璃柜中,每天2小时,连续30天。使用甲醛监测仪控制染毒柜中甲醛浓度保持在1mg/m3左右,同时保持实验环境温度、湿度恒定。采用MORRIS水迷宫测试各组大鼠的逃避潜伏期和错误次数以及跨平台次数,判断甲醛吸入对不同龄期大鼠空间学习记忆能力的影响。结果:(1)利用静式吸入染毒原理建立了大鼠甲醛吸入染毒模型,并且通过控制实验条件,使模型效果稳定、可靠,结果具有可比性;(2)本模型染毒剂量及染毒方式的设计接近环境暴露条件下人对甲醛的暴露剂量和方式,为今后的人群研究提供良好的实验依据;(3)各年龄期染毒组水迷宫平均逃避潜伏期均显著长于对照组,有统计学意义(P0.05),其中新生组差异更为显著(P 0.01);(4)成年与幼年染毒组游泳错误次数与对照组比较无显著差异(P 0.05),而新生染毒组游泳错误次数较对照组显著增加(P 0.05);(5)各年龄期染毒组跨平台次数均显著低于对照组(P 0.05)。结论:甲醛吸入染毒对大鼠空间学习记忆能力有一定的损害作用,而新生鼠对甲醛吸入染毒更加敏感。第二部分甲醛影响不同龄期大鼠认知功能的分子机制目的:探索甲醛吸入染毒影响不同龄期大鼠认知功能的病理基础和分子机制。方法:选择不同龄期的Wistar鼠36只,其中成年鼠(2-3月龄)、幼年鼠(生后20天)、新生鼠(生后1天)各12只,各年龄组大鼠随机分为对照组和染毒组,每组6只,雌雄不拘。其中染毒组大鼠置于60L有机玻璃染毒柜中,进行30天的连续染毒(甲醛浓度1mg/m3,2小时/天),对照组大鼠置于同规格的不含甲醛的有机玻璃柜中,每天2小时,连续30天。实验完成后处死实验动物。采用尼氏染色法观察各组海马形态学结构的变化;免疫组化法检测皮层和海马神经元内SYN、BDNF、NPY的表达变化。结果:(1)尼氏染色中,各年龄染毒组海马CA1区神经细胞尼氏体数量减少,分布不均,部分细胞尼氏体消失,其中幼年组和新生组神经细胞数目减少,层次紊乱;(2)免疫组化结果显示,各年龄段染毒组SYN和BDNF免疫阳性细胞平均光密度值显著低于对照组(P 0.05),且新生染毒组与对照组比较差异更加明显(P 0.01);幼年和新生染毒组NPY免疫阳性细胞平均光密度值显著低于对照组(P 0.05),而在成年组,差异无显著性(P 0.05)。结论:(1)甲醛吸入染毒可造成各年龄期大鼠海马神经元损伤,导致组织形态学变化;(2)甲醛吸入染毒后可导致各年龄期大鼠SYN、BDNF、NPY免疫阳性细胞表达显著减少;(3)甲醛染毒后海马组织形态与SYN、BDNF和NPY表达变化,均以新生组更为明显,与认知功能改变呈年龄一致性。
[Abstract]:Effects of first part of formaldehyde inhalation on cognitive function in rats with different age

Objective : To study the effect of formaldehyde inhalation on the spatial learning and memory ability of rats with different age .

Methods : 36 Wistar rats were randomly divided into control group ( 2 - 3 months ) , young mouse ( 20 days after birth ) and neonatal rats ( 1 day after birth ) .

Results : ( 1 ) By using the principle of static inhalation , the model of formaldehyde inhalation exposure was established , and the experimental conditions were controlled . The results showed that the model had stable and reliable results , and ( 2 ) the exposure dose and the way of exposure to formaldehyde were significantly longer than those in the control group ( P0.05 ) .

Conclusion : Formaldehyde inhalation has a certain effect on the learning and memory ability of rats , and neonatal rats are more sensitive to formaldehyde inhalation .

The Molecular Mechanism of the Effect of the Second Part of Formaldehyde on the Cognitive Function of Rats with Different Ages

Objective : To explore the pathological basis and molecular mechanism of cognitive function in rats with different age .

Methods : 36 Wistar rats were randomly divided into control group ( 2 - 3 months ) , young mouse ( 20 days after birth ) and neonatal rats ( 1 day after birth ) .

Results : ( 1 ) The number of neurons in CA1 region of hippocampus CA1 region was decreased and the distribution was not uniform . The number of neural cells decreased and the level was disordered in juvenile and neonatal group .

Conclusion : ( 1 ) Formaldehyde inhalation exposure can cause neuronal damage in hippocampus of rats at all ages , which leads to morphological changes of tissue . ( 2 ) The expression of SYN , BDNF , NPY immunoreactive cells in rats of different ages can be decreased significantly after inhalation of formaldehyde ; ( 3 ) The expression of SYN , BDNF and NPY in hippocampus after exposure to formaldehyde is more obvious than that in neonatal group , which is consistent with the change of cognitive function .

【学位授予单位】：重庆医科大学
【学位级别】：硕士
【学位授予年份】：2007
【分类号】：R363

【参考文献】