氟对大鼠胆碱酯酶活性和学习记忆功能的影响

目的 研究氟对慢性氟中毒大鼠学习、记忆功能的影响以及其可能的机制,探讨氟对脑组织胆碱酯酶活性的影响多氟中毒大鼠智力损伤程度的关系.方法 SD大鼠按性别和体质量随机分为3组,对照组:自由饮用自来水,含氟量低于1mg/L;低剂量染氟组:饮水含氟量为5mg/L;高剂量染氟组:饮水含氟量为50mg/L.实验3个月时检测大鼠行为学变化和脑组织胆碱酯酶活性.结果 高剂量染氟组大鼠的逃避潜伏期时间[(17.55±1.51)s]长于对照组[(12.07±0.97)s],两组比较差异有统计学意义(P＜0.05);高剂量染氟组探索实验目标次数[(2.88±0.35)次]与对照组[(4.00±0.50)次]比较,有降低趋势,但差异无统计学意义(P＞0.05);高剂量染氟组的乙酰胆碱酯酶和丁酰胆碱酯酶活性[(1.41±0.19)、(0.49±0.07)kU/g]均低于对照组[(1.88±0.13)、(1.04±0.16)kU/g)],差异均有统计学意义(P＜0.05).结论 过量氟在体内蓄积可使大鼠智力降低,脑内的胆碱酯酶活性降低可能是其机制之一.

Effects of fluoride on learning and memory and cholinesterase activity in rat brains

Objective To study the role of fluorosis on learning and memory in rat and its possible mechanisms;to explore the correlation between cholinesterase activity and the level of intelligence.Methods SD rats divides into 3 group of stochastically according to the sex and the body weight,control group treated with drinking water containing fluoride less than 1 mg/L,lower fluoride exposed group with drinking water containing fluoride 5 mg/L,and higher fluoride exposed group with drinking water containing fluoride 50 mg/L.The ability of learning and memory and cholinesterase activity were detected in the third month after experiment.Results Escape latency in higher fluoride exposed group[(17.55±1.51)s]was significantly higher than that of controls group [(12.07±0.97)s],the difference being statistically significant(P＜0.05).The numbers of crossing platforms in higher fluoride exposed group[(2.88±0.35)times]were lower than those of controls group[(4.00±0.50)times],but the difference was not statistically significant(P＞0.05).The activities of acetylcholinesterase and butylcholinesterase in higher fluoride exposed group[(1.41±0.19),(0.49±0.07)kU/g]were significantly lower than those of controls[(1.88±0.13),(1.04±0.16)kU/g],the difference had statistical significances(P＜0.05).Conclusions The results indicate that excessive fluoride can decrease the level of intelligence of rats, the declined activities of cholinesterase may be the possible pathogenetic mechanism.