中文摘要：

目的探讨氟、砷单独及其联合染毒对大鼠在新环境中的探究行为的影响及机制。方法将96只健康初断乳SPF级SD大鼠随机分为对照（蒸馏水）组和NaF（120mg／L）染毒组、亚砷酸钠（70mg／L）染毒组及NaF（120mg／L）＋亚砷酸钠（70ms／L）染毒组，每组24只，雌雄各半。采用饮水方式连续染毒3个月。采用旷场试验测试大鼠在新环境中的探究行为，检测大鼠血清和海马组织匀浆中总抗氧化能力（T-AOC）水平和丙二醛（MDA）、一氧化氮（NO）含量及超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH-px）和一氧化氮合酶（NOS）活力。结果NaF＋亚砷酸钠染毒组大鼠旷场试验总得分低于对照组、NaF和亚砷酸钠染毒组（P〈0．01）。NaF、亚砷酸钠和NaF＋亚砷酸钠染毒组中央格停留时间均长于对照组（P〈0．01）。与对照组比较，NaF、亚砷酸钠和NaF＋亚砷酸钠染毒组大鼠血清T-AOC水平及亚砷酸钠染毒组和NaF＋亚砷酸钠染毒组血清SOD、GSH-Px活力降低，MDA含量升高（P〈0．05，P〈0．01）。与NaF染毒组比较，亚砷酸钠和NaF＋亚砷酸钠染毒组大鼠血清中T-AOC水平和GSH-Px活力降低（P〈0．05，P〈0．01）。与对照组比较，NaF、亚砷酸钠和NaF＋亚砷酸钠染毒组大鼠海马组织匀浆中T-AOC水平均降低（P〈0．01）。与亚砷酸钠染毒组比较，对照组、NaF染毒组和NaF＋亚砷酸钠染毒组大鼠海马组织匀浆中GSH-Px的活力均较高（P〈0．01）。与NaF＋亚砷酸钠染毒组比较，NaF、亚砷酸钠染毒组和对照组大鼠海马组织匀浆中MDA含量均较低（P〈0．01）。与对照组比较，NaF和NaF＋亚砷酸钠染毒组大鼠血清NO含量以及NaF、亚砷酸钠和NaF＋亚砷酸钠染毒组大鼠血清中NOS活力及海马组织中NO含量、NOS活力均下降（P〈0．05，P〈0．01）。结论氟、砷及其联合作用可损害大鼠在新环境中的探究行为，其机制可?

英文摘要：

Objective To explore the effects of fluoride, arsenic and co-exposure on explore ability in novel environment and it＇s mechanism in rats. Methods The Sprague-Dawley rats were randomly divided into four groups at the beginning of weaning. Three exposure group rats were exposed to 120 mg/L sodium fluoride （NaF）,70 mg/L sodium arsenite （NaAsO2）,and 120 mg/L NaF＋70 mg/L NaAsO2 combined solution from drinking water for ninety days,respectively. The control rats drunk distilled water for ninety days. The explore ability in novel environment was evaluated by open field test. The levels of T-AOC, MDA,NO,SOD,GSH-Px and NOS were measured by using corresponding kits. Results The total scores in open field test significantly decreased in rats exposed to NaF and NaAsO2 combined solution than that in the control,NaF-exposed and NaAsO2-exposed rats （all P〈0.01）. The levels of central cell latency time in rats exposed to NaF,NaAsO2 and their combined solution were all markedly increased than that in the control rats （all P〈0.01）. Compared with the controls,the levels of T-AOC in serum of NaF-exposed, NaAsO2-exposed and co-exposed rats, the levels of SOD and GSH-Px activity in serum of NaAsO2-exposed and co-exposed rats all decreased （P〈0.05,P〈0.01）. Compared with controls,the levels of MDA in serum of NaF- exposed,NaAsO2-exposed and co-exposed rats all increased （P〈0.01,P〈0.01）. The levels of T-AOC and GSH-Px activity in serum of NaAsO2-exposed and co-exposed rats were all much lower than that in NaF-exposed rats（P〈0.05 ,P〈0.01）. The levels of T-AOC in hippocampus of NaF-exposed, NaAsO2-exposed and co-exposed rats were all much lower than controls（P〈0.01 ）. The GSH-Px activity in NaAsO2-exposed rats was much lower than the other three group rats（all P〈0.01）. The level of MDA in NaAsO2-exposed rats was much higher than the control（P〈0.01）, NaF-exposed rats（P〈0.05） and NaAsO2-exposed rats （P〈0.05）. The contents of NO in serum of NaF-exposed and co-expose