摘要目的 观察长期低剂量饮水砷暴露对不同代次C3H和Balb/c小鼠学习认知能力的影响.方法 选取C3H和Balb/c小鼠(雌鼠各20只,雄鼠各10只),自由饮用0(对照组)、85 mg/L亚砷酸钠(NaAsO2)溶液(砷暴露组),并连续传代(F).分别选取对照组和砷暴露F1 、F2 、F3 、F4代的C3H和Balb/c小鼠,每组8只.通过Morris水迷宫,测定小鼠空间记忆能力(第1、2、3、4、5天测定登上平台的潜伏期)和空间探索能力(第6天测定穿越目标区域平均次数),SPSS 18.0软件进行统计分析.结果 第1、2、3、4、5天C3H小鼠潜伏期对照组为(48.09±2.63)、(46.09±3.27)、(42.72±3.29)、(39.31±2.69)、(36.75±3.92)s;F1代为(49.59±3.29)、(47.34±3.01)、(44.28±6.58)、(44.50±1.67)、(42.16±2.27)s;F2代为(51.41±0.78)、(48.88±1.45)、(45.54±1.46)、(43.94±1.69)、(42.22±3.27)s;F3代为(50.91±4.20)、(49.78±5.18)、(48.03±3.45)、(46.16±4.42)、(44.06±1.04)s;F4代为(52.66±4.60)、(52.38±5.78)、(49.06±1.22)、(47.69±2.34)、(46.47±1.56)s. Balb/c小鼠潜伏期对照组为(50.91±2.84)、(47.03±4.22)、(45.56±4.53)、(39.72±5.90)、(36.22±4.85)s;F1代为(50.47±3.20)、(48.25±6.53)、(47.13±1.25)、(43.72±4.27)、(40.66±4.52)s;F2代为(51.31±4.73)、(48.88±1.53)、(46.56±1.43)、(44.25±1.16)、(41.20±3.79)s;F3代为(51.72±3.54)、(50.78±4.45)、(45.03±3.56)、(41.19±5.63)、(42.81±6.29)s;F4代为(53.34±4.60)、(52.34±2.77)、(48.72±5.92) 、(46.97±7.38)、(44.94±1.75)s.第4、5天F1、F2、F3、F4代C3H小鼠潜伏期与同时间对照组比较,差异有统计学意义(P均＜ 0.05).第6天穿越目标区域平均次数对照组和F 1、F2、F3、F4代C3H小鼠分别为2.25、1.75、1.63、1.50、1.38次,Balb/c小鼠分别为2.13、1.75、1.63、1.38、1.13次.结论体内砷蓄积可使连续传代的C3H和Balb/c小鼠学习认知能力明显下降.

abstractsObjective To observe the effects of long-term low dose arsenic exposure through drinking water on learning ability of different generations of C3H and Balb/c mice.Methods Mice (C3H and Balb/c) were exposed to arsenic at 0 mg/L (control) and 85 mg/L (20 female mice and 10 male mice per group).The control group and F1,F2,F3 and F4 mice were selected and divided into 5 experimental groups,8 mice in each group.Their offsprings were detected by the Morris water maze test (the average escape latency of 1 to 5 days) and spatial probe test (the times of through target area on the sixth day).Statistical analysis was performed with SPSS 18.0 software.Results The average escape latencies of 1 to 5 days in C3H control group were (48.09 ± 2.63),(46.09 ± 3.27),(42.72 ± 3.29),(39.31 ± 2.69) and (36.75 ± 3.92) s,F1 were (49.59 ± 3.29),(47.34 ± 3.01),(44.28 ± 6.58),(44.50 ±1.67) and (42.16 ± 2.27) s,F2 were (51.41 ± 0.78),(48.88 ± 1.45),(45.54 ± 1.46),(43.94 ± 1.69) and (42.22 ± 3.27) s,F3 were (50.91 ± 4.20),(49.78 ± 5.18),(48.03 3.45),(46.16 ± 4.42) and (44.06 ± 1.04) s,F4 were (52.66 ± 4.60),(52.38 ± 5.78),(49.06 ± 1.22),(47.69 ± 2.34) and (46.47 ± 1.56) s.The average escape latencies of Balb/c control group were (50.91 ± 2.84),(47.03 ± 4.22),(45.56 ± 4.53),(39.72 ± 5.90) and (36.22 ± 4.85) s,F1 were (50.47 ±3.20),(48.25 ± 6.53),(47.13 ± 1.25),(43.72 ± 4.27) and (40.66 ± 4.52) s,F2 were (51.31 ± 4.73),(48.88 ± 1.53),(46.56 ± 1.43),(44.25 ± 1.16) and (41.20 ± 3.79) s,F3 were (51.72 ± 3.54),(50.78 ± 4.45),(45.03 ± 3.56),(41.19 ±5.63) and (42.81 ± 6.29) s,F4 were (53.34 ± 4.60),(52.34 ± 2.77),(48.72 ± 5.92),(46.97 ± 7.38) and (44.94 ± 1.75) s.On the fourth and fifth days of F1,F2,F3 and F4 generations of C3H,the escape latencies between generations were significantly different (all P ＜ 0.05).The times of through target area in the sixth day of the C3H control group and F1,F2,F3 and F4 mice were 2.25,1.75,1.63,1.50 and 1.38,Balb/c were 2.13,1.75,1.63,1.38 and 1.13.Conclusion Arsenic accumulation due to serial passage of C3H and Balb/c through long-term low doses arsenic exposure through drinking water has resulted in decreased learning and memory ability.