印刷油墨挥发物对小鼠认知行为及脑组织氨基酸类神经递质的影响

Effects of printing inks volatile on cognitive behavior in novel environment and amino acid neurotransmitters in brain tissue of mice

目的探讨印刷油墨挥发物暴露对小鼠认知行为及脑组织中氨基酸类神经递质的影响。方法将30只健康SPF级雄性昆明小鼠随机分为3组,分别为对照组、新闻纸油墨组和铜版纸油墨组,每组10只。采用静式吸入方式进行染毒,新闻纸油墨组、铜版纸油墨组的平均染毒浓度分别为152、270 mg/m^3,每日1次,每次2 h,每周6 d,持续染毒4周。采用水迷宫和旷场试验测试小鼠的认知行为变化,并检测小鼠脑组织中谷氨酸(Glu)、甘氨酸(Gly)、γ-氨基丁酸(GABA)及天冬氨酸(Asp)的含量。结果与对照组相比,新闻纸油墨组和铜版纸油墨组小鼠首次达台时间均延长,目标象限时间均缩短,穿台次数均减少,差异有统计学意义(P<0.05);与新闻纸油墨组相比,铜版纸油墨组小鼠首次达台时间均延长,目标象限时间均缩短,穿台次数均减少,差异有统计学意义(P<0.05)。与对照组相比,新闻纸油墨组及铜版纸油墨组小鼠在中央格停留时间延长,水平穿越格子数、直立次数均下降,仅铜版纸油墨组小鼠的修饰次数下降,差异均有统计学意义(P<0.05)。与新闻纸油墨组相比,铜版纸油墨组小鼠在中央格停留时间延长,水平穿越格子数、直立次数均下降,差异均有统计学意义(P<0.05);而修饰次数无明显变化。与对照组相比,新闻纸油墨组及铜版纸油墨组小鼠脑组织Glu、Gly、GABA、Asp的含量均下降,差异均有统计学意义(P<0.05)。与新闻纸油墨组相比,铜版纸油墨组小鼠脑组织Glu、GABA、Asp的含量均下降,差异均有统计学意义(P<0.05);而Gly的含量无明显变化。结论油墨挥发物暴露可影响小鼠的记忆及探究行为,并可致脑组织氨基酸类神经递质分泌减少。

Objective To understand the effects of printing ink volatiles on cognitive behavior and amino acids neurotransmitter in mice brain. Methods A total of 30 healthy SPF male Kunming mice were randomly divided into three groups, 10 in each group, the control group, newsprint ink group and coated paper ink group, exposed by static inhalation manner. The average exposure concentrations of newsprint ink group and coated paper ink group was 152,270 mg/m3, 2 hours once a day, 6 days a week for 4 weeks. Cognitive behavioral changes in mice was tested by water maze and open field trials, and glutamate（Glu）,glycine（Gly）, γ-aminobutyric acid（GABA） and aspartic acid（Asp） contents in mice brain was also tested. Results Compared with control group, time of first sets in newsprint and coated paper ink group was prolonged, the target quadrant time was shortened, wear sets number was reduced, and the difference was statistically significant（P〈0.05）. Compared with newsprint ink set, time of first sets in coated paper ink group was prolonged, the target quadrant time was shortened, wear sets number was significantly reduced（P〈0.05）. Compared with control group, mice in newsprint and coated paper ink group stayed longer at the center grid, level crossing grid number and upright number decreased, only the modified number of coated ink group significantly decreased（P 0.05）. Compared with newsprint ink group, mice in coated paper ink group stayed longer at the center grid, level crossing grid number and upright number decreased with no significant change in modified number, and the differences were statistically significance（P 0.05）;Compared with the control group, Glu, Gly, GABA and Asp contents in mouse brain of newsprint and coated ink group were significantly decreased（P〈0.05）. Compared with newsprint ink group, Glu,GABA and Asp contents in mouse brain of coated ink group were decreased statistically（P〈0.05）,but there was no significant change in Gly content. Conclusion Ink volatiles exposure can affect memory and exploratory behavior and reduce amino acid neurotransmitters secretion in brain of mice.