孕鼠氟暴露对仔鼠学习记忆能力影响

Influence of fluorosis on learning memory of pup rats and activities of SOD and content of MDA in brain

目的探讨孕鼠氟暴露通过胎盘屏障对仔鼠学习记忆能力影响及可能机制。方法采用开场行为、水迷宫试验观察孕鼠饮用不同浓度氟化钠溶液对仔鼠自发行为、学习记忆的影响,检测仔鼠脑内超氧化物歧化酶(SOD)活性及丙二醛(MDA)含量。结果与对照组(33.91±7.36)比较,低氟组仔鼠站立次数(44.64±4.73)明显增多(P<0.01);与对照组比较,低氟组和高氟组粪便颗粒明显减少(P<0.01),中氟组、高氟组仔鼠3 min内移动格数明显减少(P<0.01或P<0.05);中氟组和高氟组仔鼠1 min内移动格数分别为(44.82±9.74),(40.60±11.29),明显低于低氟组的(57.93±14.64)(P<0.01);与对照组比较,中氟组和高氟组仔鼠学习能力有下降趋势;高氟组仔鼠脑内SOD活性(490.43±48.86)U/mL明显低于对照组(543.54±36.72)U/mL,各染氟组仔鼠脑内MDA含量有升高的趋势。结论孕鼠氟暴露可通过胎盘屏障对仔鼠学习记忆能力产生一定影响,并可能与脑内SOD活性及MDA含量有关。

Objective To observed whether the pregnant rats fluorosis could influence the capability of learning-memory behavior of pup rats. Methods Open-field and Morris tests were conducted after the pregnant rats drinking different concentration of NaF for a long time. The learning-memory behavior, the varieties of the activity of superoxide dismutase （SOD）, and the content of malonaldehyde （MDA） in pup rats＇ brain were investigated. Results Compared with the control group, the number of standing for low-fluoride group rats increased markedly（ P 〈 0.01 ）. The fecal particles of the low and high-fluoride group significantly reduced. The ambulation in three minutes for rats of the middle and high-fluoride group decreased significantly（ P 〈 0.01, P 〈 0.05 ）. Compared with the low-fluoride group, the ambulation in one minute of the middle and high fluoride groups decreased significantly（ P 〈 0.01 ）. Compared with the control group,the learning ability of middle and high fluoride groups presented deterioration. The activity of SOD in pup rats＇ brain in high fluoride groups was lower than that of the control group （ P 〈 0.05 ）. There was an increase trend for the content of MDA in pup rats. Conclusion Fluorosis of pregnant rats had significant adverse effects on open-field behavior, the capacity of learning, the activity of SOD, and the content of MDA in pup rats.