钇对子代大鼠神经行为和认知能力的影响

目的研究硝酸钇对子代大鼠神经行为和认知能力的影响。方法将孕鼠随机分为对照和受试物低、中、高4个试验组,20只/组。从孕期第6天(GD 6)至分娩后第21天(PND 21),受试物组每天分别灌胃给予硝酸钇溶液5、15、45 mg/kg BW,对照组灌胃给予蒸馏水。断乳后,继续给予子鼠原剂量受试物直至PND 63天。观察不同剂量硝酸钇对子鼠生长发育、脏器组织和神经行为的影响。结果在PND 21天时,雄鼠低、中、高3个剂量组体重均高于对照组,且差异有统计学意义(P0.05)。但从PND 42天开始至试验结束,雄性高剂量组体重明显低于对照组,导致高剂量组雄鼠总增重和总进食量均低于对照组,且差异有统计学意义(P0.05),但食物利用率无变化。PND 42天时雌鼠低剂量组体重和雄鼠高剂量组脑体比均高于对照组,且差异有统计学意义(P0.05),但不认为有生物学意义。Morris水迷宫试验中仅高剂量组雌鼠第5天的潜伏期高于对照组,且差异有统计学意义(P0.05),其他神经行为试验结果均未见差异。结论在本试验条件下,断乳后持续给予硝酸钇受试物会导致高剂量组雄性子鼠的体重下降,但不会影响脑组织重量,也不会在成年早期对子鼠的痛觉、运动活力和认知能力等神经行为造成影响。

Study on the neurobehavior and cognitive ability of rat offspring exposed to yttrium nitrate

To assess the neurobehavior and cognitive ability of rat offspring exposed to yttrium nitrate.Methods Pregnant rats were orally exposed to yttrium nitrate by garage at 0,5, 15 or 45 mg/kg BW dose from gestation day (GD) 6 to postnatal day (PND) 21, then offspring were given the same dose until PND 63. The indexes of body weights, food consumption, organ weights and neurobehavior test results such as hot plate, motor activity and Morris water maze test were recorded. Results All yttrium-exposed male offspring showed a significantly increased body weight on PND 21. However, male offspring body weight of 45 mg/kg BW dose decreased significantly from PND 42 to the end of the experiment (P<0.05), which caused a lower weight change and overall food consumption (P<0.05), but all groups showed similar feed conversion ratios. The differences on other body weight and relative brain weight between treated and control groups were not considered treatment-related. The only significant difference in Morris water maze test was the high dose female offspring which showed a higher latency on the fifth day (P<0.05), and similar results were observed among other neurobehavior tests.Conclusion Continual exposure of yttrium nitrate could cause a decline in the body weight of high dose male offspring, but would not affect the brain weight. Moreover, no differences were found in tests of hot plate, motor activity and Morris water maze test.