中文摘要：

目的探讨氟、砷及其联合染毒对仔鼠空间学习记忆能力及脑组织中磷脂酰肌醇激酶（PI3K）和苏氨酸激酶（AKT）蛋白表达的影响。方法将32只SPF级SD孕鼠随机分为4组,分别为对照（自来水）组、氟（100 mg/L Na F）染毒组、砷（75 mg/L亚砷酸钠）染毒组和联合（100 mg/L Na F＋75 mg/L亚砷酸钠）染毒组,每组8只。从妊娠第0天至仔鼠出生后21 d（postnatal day 21,PND21）,孕鼠经自由饮水方式进行染毒,断乳（PND21）后仔鼠饮用与母鼠相同浓度的染毒溶液继续染毒至PND42。采用Morris水迷宫检测PND21和PND42仔鼠的空间学习记忆能力,采用Western blot方法检测海马和大脑皮质组织中PI3K、AKT和磷酸化AKT（p-AKT）蛋白的表达水平。结果训练第1天时,仅砷染毒组PND21仔鼠的逃避潜伏期长于对照组;训练第11天时,仅联合染毒组PND21仔鼠的逃避潜伏期长于氟染毒组,差异均有统计学意义（P〈0.05）。与对照组相比,训练第4天及第11天时联合染毒组PND21仔鼠首次到达平台时间均较长;训练第4天时砷染毒组PND21仔鼠的目标象限停留时间较短,联合染毒组PND21仔鼠的穿台次数较少,差异均有统计学意义（P〈0.05）。训练第11天时,仅砷染毒组PND21仔鼠的穿台次数少于氟染毒组,差异有统计学意义（P〈0.05）。与对照组、氟染毒组相比,砷染毒组和联合染毒组PND42仔鼠在训练第1天和第11天的逃避潜伏期时间均延长;且联合染毒组PND42仔鼠在训练第2天的逃避潜伏期长于对照组和砷染毒组,差异均有统计学意义（P〈0.05）。训练第4天时,联合染毒组PND42仔鼠的首次到达平台时间长于对照组和氟、砷染毒组;联合染毒组和氟、砷染毒组PND42仔鼠的目标象限停留时间均短于对照组,穿台次数少于对照组;且联合染毒组和砷染毒组PND42仔鼠的穿台次数少于氟染毒组,差异均有统计学意义（P〈0.05）。训练第11天时,联合染毒组和?

英文摘要：

Objective To explore the effects of single and combined exposure of fluoride and arsenic on spatial learning and memory ability and PI3 K and AKT protein expression in the brain of offspring of rats. Methods A total of 32 Sprague-Dawley pregnant rats were randomly divided into four groups, eight in each. During the gestation and lactation periods（about three weeks）, the rats in the three exposure groups were exposed to 100 mg/L sodium fluoride（Na F）, 75 mg/L sodium arsenite（Na As O2）, and 100 mg/L Na F and 75 mg/L Na As O2 in drinking water, respectively. The control rats were provided drinking water without supplements. Morris water maze was used to measure the spatial learning and memory ability of pups in PND21 and PND42, respectively. Then the protein expression levels of PI3 K, AKT and phosphorylated AKT（p-AKT） in hippocampus and cerebral cortex of pup rats were detected by Western blot assay. Results The escape latency period on training day 1 of PND21 pups in arsenic group was significantly higher than that in control group（P〈0.05）. The escape latency period（training day 11） of PND21 pups in fluoride plus arsenic group was significantly higher than that in fluoride group（P〈0.05）. Compared with the control, the first platform time（training day 4 and day 11） of PND21 pups exposed to fluoride and arsenic in combination significantly prolonged（P〈0.05）, the target quadrant time on training day 4 of PND21 pups in arsenic group was markedly shortened（P〈0.05）, the frequency through the platform within 120 s on training day 4 of PND21 pups in fluoride plus arsenic group was much less（P〈0.05）, the frequency through the platform within 120 s on training day 11 of PND21 pups in arsenic group was much less（P〈0.05）. The escape latency period（training day 4 and day 11） of PND42 pups in arsenic and fluoride plus arsenic group were significantly higher than that in control and fluoride group, pups in fluoride plus arsenic group on training day 2 was higher tha