氧化钕经鼻滴注对小鼠神经系统的影响

Effect of Neodymium Oxide by Nasal Drip on Nervous System in Mice

研究氧化钕经鼻滴注对小鼠神经系统的影响,进一步考察氧化钕的神经毒性是否存在剂量和尺寸效应。选取健康的ICR雌鼠48只,随机分为对照组、低剂量纳米(L-nm)氧化钕组(1μg/mL)、高剂量纳米(H-nm)氧化钕组(40μg/mL)和低剂量微米(L-μm)氧化钕组(1μg/mL)。经鼻染毒,共10d,隔天1次;染毒第2次之后进行水迷宫试验,定位航行试验7d,1d一个单元,同时在第7天进行空间探索试验;取血,进行生化指标检测;取脑置于100g/L甲醛溶液固定,常规脱水,石蜡包埋、切片,苏木素-伊红(HE)染色。剂量效应显示,不同浓度纳米氧化钕对小鼠经鼻滴注,高纳米组与低纳米组相比,目标象限游程占总游程百分比较高(P<0.05),但在此尺寸条件下剂量效应不明显。尺寸效应显示,相同浓度纳米氧化钕对小鼠经鼻滴注,L-μm组海马颗粒细胞排列稀疏,细胞脱落;L-nm组海马齿状回颗粒细胞排列较整齐,可见部分细胞核固缩在此试验浓度条件下尺寸效应不明显。血液生物标志物检查试验显示,氧化钕经鼻滴注会对小鼠肝功能、肾功能产生一定的损伤。不同浓度纳米氧化钕经鼻滴注,对小鼠有轻微的刺激学习记忆的作用,但剂量效应不明显。低微米氧化钕对小鼠神经系统有轻微的损伤,但与低纳米氧化钕相比,差异不显著,表明尺寸效应不明显。

To study the effect of nasal instillation of neodymium oxide on nervous system in mice, and to further evaluate the neurotoxicity of neodymium oxide, a total of 48 healthy famale ICR mice （about 20 g） were randomly divided into control group, low （1μg/mL）, high nano groups （40μg/mL）, low micron group （1μg/mL）. Nasal instillation,a total of 10 days,once every other day. The water maze experiment were conducted after the second nasal instillation,navigation experiment 7 days,one day a unit,space exploration experiments at the same time on the seventh day. Blood samples were taken for biochemical tests. The brain was fixed in 100 g/L formaldehyde solution, dehydrated, embedded in paraffin, sliced and hema- toxylin-eosin （HE） stained. Dose-effect study：Compared with the low nanometer group, the percentage of the target quadruple run was higher （P〈0.05） ,but the dosage effect was not obvious under the condition of the nasal instillation of different concentrations of neodymium oxide nanoparticles. Size-effect study. In the L-nm group, the number of granulosa cells in the hippocampal dentate gyrus was higher than that in the L-nm group,and the number of nuclei in the L-nm group was higher than that in the L-nm group. The size effect was not significant at this experimental concentration. Blood biomarker examination experiments showed that：neodymium oxide nasal drip in mice have some damage to liver function,renal function. Differ- ent concentrations of nano-neodymium oxide in mice by nasal drip may have a slight stimulation of the role of learning and memory,but the dose effect is not obvious. Low-micron neodymium has a slight damage to the nervous system in mice, but the difference is not significant compared with the low-nano-neodymium oxide,indicating that the size effect is not obvious.