气态甲醛致中枢神经毒性效应及其机理探讨

发布时间：2018-02-03 00:43

本文关键词： 甲醛神经毒性 Motris水迷宫氧化损伤 NMDA受体　出处：《华中师范大学》2006年硕士论文　论文类型：学位论文

【摘要】：甲醛(formaldehyde,FA)是一种常见的装修型化学性室内空气污染物,也是一种内源性有机化合物。室内空气甲醛对人体健康的影响涉及:呼吸道和眼部刺激作用、致敏作用和免疫毒性、遗传毒性和癌症、肺功能损害、神经行为改变等诸多方面。本课题对气态甲醛对中枢神经的毒性效应进行了研究,并对其可能机制进行了探讨。采用浓度为0mg/m~3、0.5mg/m~3、1.0mg/m~3和3.0mg/m~3气态甲醛对昆明小鼠进行吸入式染毒(6h×7d),同时进行Morris水迷宫实验(包括定位航行实验和空间探索实验)检测小鼠空间学习与记忆的能力,并在染毒结束后进行脑组织氧化损伤水平的测定。另外采用3.0mg/m~3的气态甲醛对BALB/C小鼠进行吸入式染毒(6h×7d),染毒结束后立即取前脑组织,应用半定量RT-PCR方法检测其N—甲基-D-天冬氨酸(NMDA)受体亚基Grinl,Grin2a,Grin2b基因mRNA的表达水平。结果显示,定位航行实验各组小鼠的逃逸潜伏期均随实验天数的增加而下降,实验天数(F=17.83,P0.01)和不同浓度的甲醛吸入(F=8.84,P0.01)对逃逸潜伏期均有极显著影响,但二者没有交互作用。对不同浓度甲醛吸入组采用新复极差法进行多重比较,结果显示0mg/m~3甲醛吸入组与0.5mg/m~3、1.0mg/m~3甲醛吸入组之间无显著差异,与3.0mg/m~3甲醛吸入组之间有极显著差异(P0.01)。空间探索实验中0mg/m~3和0.5mg/m~3甲醛吸入组小鼠均在平台所在象限的游泳时间较长,在其它象限的游泳时间相对较短。0mg/m~3甲醛吸入小鼠在平台象限(NE)的游泳时间与SE象限的游泳时间相比存在显著差异(P0.05),与NW、SW象限的游泳时间之间则存在极显著差异(P0.01)。0.5mg/m~3甲醛吸入组小鼠在NE象限的游泳时间与其它三个象限相比均有极显著差异(P0.01),并且其在NE象限的游泳时间显著长于对照组小鼠(P0.01)。在3.0mg/m~3甲醛吸入组中,小鼠在SE象限的游泳时间最长,在平台象限的游泳时间与NE和SW两象限相差不大。氧化损伤水平检测中,1.0mg/m~3和3.0mg/m~3甲醛吸入小鼠的丙二醛(MDA)含量与对照组相比极显著升高(P0.01),3.0mg/m~3甲醛吸入组与对照相比,其谷胱甘肽(GSH)含量和超氧化物歧化酶(SOD)活力均极显著降低(P0.01)。 NMDA受体的mRNA表达水平变化为:甲醛吸入组与对照组相比Grinl的表达显著上调(P0.05),Grin2b亚基的表达水平极显著上升(P0.01),Grin2a基因表达极显著下调(P0.01)。
[Abstract]:Formaldehyde formaldehydefa is a common chemical indoor air pollutant and an endogenous organic compound. The effects of formaldehyde in indoor air on human health include respiratory tract and eye irritation, sensitization and immunotoxicity. In this paper, the toxic effect of gaseous formaldehyde on central nervous system was studied and its possible mechanism was discussed. Kunming mice were exposed to inhaled formaldehyde at concentrations of 0 mg / m ~ (3) 0 mg / m ~ (3) 0 mg / m ~ (3) and 3.0 mg / m ~ (-3) gaseous formaldehyde for 6 h 脳 7 d ~ (-1) respectively. Meanwhile, Morris water maze test (including positioning navigation experiment and space exploration experiment) was performed to examine the ability of spatial learning and memory in mice. The level of oxidative damage of brain tissue was measured after exposure. In addition, inhaled BALB/C mice were exposed to gaseous formaldehyde of 3.0 mg / m ~ (3) for 6 h 脳 7 d, and forebrain tissue was taken immediately after exposure. The expression of Grin2a Grin2b receptor subunit Grin2a Grin2b gene was detected by semi-quantitative RT-PCR method. The results showed that the escape latency of each group decreased with the increase of the experimental days, and the days of the experiment were significantly affected by different concentrations of formaldehyde inhaled FG 8.84 (P0.01), and the results showed that the escape latency of the mice decreased with the increase of the experimental days, and the days of the experiment were significantly affected by the different concentrations of formaldehyde inhaled FU 8.84 (P0.01). But there was no interaction between the two groups. The results showed that there was no significant difference between 0 mg / m3 formaldehyde inhalation group and 0.5 mg / m ~ (3) 1 mg / m ~ (3) formaldehyde inhalation group, but there was a very significant difference between 0 mg / m ~ (-3) formaldehyde inhalation group and 3.0 mg / m ~ (3) formaldehyde inhalation group (P0.01). In the space exploration experiment, the mice in the 0 mg / mt3 and 0.5 mg / mt3 formaldehyde inhaled groups had a longer swimming time in the quadrant where the platform was located. The swimming time in other quadrants was relatively short. 0 mg / m3 formaldehyde inhalation in the platform quadrant.) there was a significant difference between swimming time in SE quadrant and that in SE quadrant, and there was a significant difference between swimming time in other quadrants and swimming time in NWW quadrant. Compared with the other three quadrants, the swimming time of the formaldehyde inhalation group was significantly different from that of the other three quadrants, and the swimming time in the NE quadrant was significantly longer than that in the control group (P 0.01). The swimming time of mice in SE quadrant was the longest, but the swimming time in platform quadrant was not different from that in NE and SW quadrants. Compared with the control group, the content of malondialdehyde (MDAA) in mice exposed to 1.0 mg / mm3 and 3.0 mg / mm3 formaldehyde was significantly higher than that in the control group, and the GSH content and the activity of superoxide dismutase (SOD) in the control group were significantly lower than those in the control group. The changes of mRNA expression of NMDA receptor were as follows: compared with the control group, the expression of Grinl in formaldehyde inhaled group was significantly up-regulated, and the expression level of P0.05Agrin2b subunit was significantly increased. The expression of P0.01-Grin2a gene was significantly down-regulated in the formaldehyde inhaled group compared with the control group.
【学位授予单位】：华中师范大学
【学位级别】：硕士
【学位授予年份】：2006
【分类号】：R363

【引证文献】