【摘要】 目的研究不同剂量碘化物对子代小鼠学习记忆能力的影响,比较不同试验组间仔鼠海马组织bcl-2、bax基因表达差异,并进行相关性分析。方法选取初断乳清洁级昆明种小鼠96只（雌鼠56只,雄鼠40只）,按性别、体质量随机分为8组,每组雌鼠7只,雄鼠5只。各组小鼠分别饮用含碘量为50、180、1000、5000μg/L的碘化钾（KI）或碘酸钾（KIO₃）去离子水（各组浓度以碘离子计）。试验动物自由饮水、食用常规饲料、雌雄分开饲养。试验动物饲养第60日,同组雌雄小鼠合笼,待雌鼠怀孕将其分开饲养,（21±2）d雌性小鼠产下仔鼠。仔鼠断乳后继续饮用与母代相同的水60 d。各试验组随机选择10只小鼠进行试验。应用Morris水迷宫试验测定子代小鼠的学习记忆能力,采用半定量逆转录聚合酶链反应（RT-PCR）测定小鼠海马组织中Bcl-2、bax基因表达相对量。结果（1）在Morris水迷宫定位航行试验中,随着训练次数的增加,子代小鼠的逃避潜伏期呈下降趋势,差异有统计学意义（F=257.857,P=0.000）;各试验组间小鼠的逃避潜伏期不全相同,差异有统计学意义（F=3.012,P=0.008）;训练次数与试验干预两变量间有交互作用（F=2.529,P=0.001）。（2）各试验组bcl-2基因mRNA表达水平不完全相同,差异有统计学意义（F=15.625,P=0.000）;各试验组bax基因mRNA表达水平不完全相同,差异有统计学意义（F=15.458,P=0.000）;各试验组bcl-2/Bax比值不完全相同,差异有统计学意义（F=13.164,P=0.000）。（3）仔鼠Morris水迷宫试验逃避潜伏期第i（i=1,2,3,4,5）日测定结果与海马组织bcl-2/bax基因mRNA表达比值显著相关（P_i=0.000）。结论母鼠及其子代小鼠持续摄入高浓度碘化物,可导致仔鼠海马组织损伤、学习记忆能力下降。更多还原

【Abstract】 Objective To study the effect of different doses of iodide on the learning and memory ability of offspring mice.Furthermore,the gene expression levels of bcl-2 and bax in the hippocampal tissues of offspring mice in different experimental groups were compared and the correlation analysis was conducted.Methods Ninty-six weaned Kunming mice（56 females,40 males） were randomly divided into 8 groups by gender and weight,with 7 females and 5 males in each group.Every group of mice drank potassium iodide（KI） or potassium iodate（KIO₃） deionized water with iodine content of 50μg/L,180 μg/L,1000μg/L and 5000μg/L,respectively.The tested female and male animals were housed separately with free access to water and normal diet for 60 days.Then,the male and female mice of the same group were housed into the same cage.When the female mice are pregnant,they were separated again.After（21 ±2） days,the female mice gave birth to the offspring mice which continued to drink the same water as their mothers do for 60 days after the weaning.Ten mice were randomly selected from each group for experiments.Morris water maze was performed to test the ability to learn and memory of the offspring mice and semi-quantitative reverse transcription polymerase chain reaction（RT-PCR） was conducted to determine the relative amount of bcl-2 and bax gene expression in hippocampal tissues of the offspring mice.Results 1.In the Morris water maze navigation test,the latency to escape of the offspring mice tended to decrease with the increase of the number of training and the difference is statistically significant（F=257.857.P=0.000）;the latency to escape among different groups was different significantly（F=3.012,P=0.008）;there was an interaction between the number of training and test interventions（F=2.529,P=0.001）.2.The bcl-2 and bax gene mRNA expression levels of different groups were different significantly（F=15.625,P=0.000）,（F=15.458,P=0.000）;the bcl-2 / bax ratios of different groups were different significantly（F=13.164,P=0.000）.3.The results of the latency to escape on the i^thg（i=l,2,3,4,5） day in the Morris water maze test were significantly correlated with the bcl-2/bax mRNA gene expression ratio in hippocampal tissues（P,=0.000）.Conclusion Maternal and offspring mice at high intake of iodine display injury in hippocampus tissue and decline of learning and memory ability.更多还原