不同剂量锰暴露对幼鼠学习记忆能力的影响  

Effects of different levels manganese exposure on learning and memory in neonate rats

作　　者：付欢欢[1,2] 余晓丹[1,2] 余晓刚 任天虹 李娈娈[1,2] 杨鑫 

机构地区：[1]环境与儿童健康教育部和上海市重点实验室,上海200092 [2]上海交通大学附属新华医院儿童与青少年保健科

出　　处：《中华行为医学与脑科学杂志》2012年第11期964-967,共4页Chinese Journal of Behavioral Medicine and Brain Science

基　　金：上海科委自然基金项目（11ZR1429800）

摘　　要：目的研究不同剂量锰暴露对幼鼠空间学习记忆的影响。方法刚出生的幼鼠随机分为对照组（生理盐水）和MnCl210，20，30mg／kg组。每组1窝10只，给予腹腔注射生理盐水，自出生之日起，每日1次给予腹腔注射MnCl2溶液直至21d龄断奶。采用旷场实验观察幼鼠活动力；应用水迷宫检测大鼠空间学习及记忆能力。采用ICP：MS检测各组幼鼠的血锰以及海马组织锰含量。结果1）对照组和10，20，30mg／kg组幼鼠的血锰水平分别为（35．58±13．77）μg/L，（80．00±12．98）μg/L，（238．51±31．43）μg/L，（348．47±34．07）μg/L；海马锰含量分别为576．82±79．78）μg/L，（798．33±40．60）μg/L，（1017．23±117．23）μg/L，（1278．76±281．48）μg/L]。染锰组幼鼠血锰和海马锰含量比对照组均明显增高（P〈0．01），且海马锰含量与血锰水平呈正相关（OR=0．91，95％CI=0．81—0．96，P〈0．01）。2）旷场试验结果显示，各组活动的总距离差异无统计学意义（F=1．79，P〉0．05），表明锰暴露对幼鼠的运动活力没有影响；3）隐蔽平台实验中，仅在第3天，染锰组幼鼠到达隐蔽平台的时间比对照组显著延长（P〈0．01）。对照组及10，20，30mg／kg组幼鼠的逃避潜伏期分别为（21．77±7．10）s，（33．78±9．95）s，（37．17±13．68）s，（41．92±16．74）s，各染锰组间平均逃避潜伏期虽随着剂量的增加而延长，但差异无统计学意义。而其余训练天数各组幼鼠逃避潜伏期比较差异无统计学意义。探索实验结果显示，各组幼鼠的速度、穿台次数和在平台象限活动的时间均没有显著差异。结论幼鼠锰暴露致使学习能力下降，但无明显的剂量效应关系；锰暴露对记忆能力没有影响。Objective To observe the effects of different levels manganese （Mn） on spatial learning and memory in neonate rats. Methods Neonate rats were distributed to control （normal saline） and MnC1210,20, 30mg/kg groups randomly. Each groups included 10 litters in a cage with a dam. Neonate rats were intraperitoneal injection exposed to MnC12 over PND 1-21. All groups were evaluated behavioral performance using open field and Morris water maze. Blood and hippocampus Mn levels were determined using ICP-MS. Results 1 ） For each group,blood Mn were （35.58 ±13.77）μg/L, （80.00 ±12.98）μg/L, （238.51 ±31.43） μg/L, （348.47 ± 34.07 ） μg/L and hippocampus Mn were （576.82 ±79.78 ） μg/L, （798.33 ±40.60） μg/L, （ 1017.23 ± 117.23 ）μg/L, （1278.76 ± 281.48 ）μg/L respectively. Blood and hippocampus Mn concentrations in Mn-exposed groups were significant increased compared to control（P〈 0.01 ）, and there was a positive correlation in blood Mn and hip- pocampus Mn （ OR = 0.91,95 % CI = 0.81-0.96, P 〈 0.01 ）. 2 ） There were no significant differences on travelled distance in open field among all groups, which meant that Mn exposure had no effect on their locomotion. 3 ） In the hidden platform trials of the Morris water maze test, only on 3rd day, Mn-expose groups spent more time to find the platform compared to the control（P 〈 0.01 ）. The average escape latency were（21.77 ±7.10）s, （33.78 ±9.95 ） s, （ 37.17 ± 13.68 ） s, （ 41.92 ±16.74） s respectively . Though the latency were increased with the Mn exposure levels increasing among the Mn-expose groups, no statistically significant differences were observed. There were no statistically effects on latency to find the platform of all groups in other training days. The result in probe trails showed that there were no statistically effects on swimming velocity, the number of crossing over the former platform and the time spent in the targeted quadrant. Conclusion Mn exposure exerts effects on the lea

关 键 词：锰暴露 幼鼠 旷场试验 MORRIS水迷宫 学习记忆 

分 类 号：R285.5[医药卫生—中药学]