Rodríguez V M, Carrizales L, Mendoza M S, Fajardo O R, Giordano M
Center for Neurobiology, Campus UNAM-Juriquilla, P.O. Box 1-1141, Qere'taro, Qro. 76001, Mexico.
Neurotoxicol Teratol. 2002 Nov-Dec;24(6):743-50. doi: 10.1016/s0892-0362(02)00313-6.
Arsenic is an environmental contaminant found in soil, water and air in some zones of the world. It has been widely studied for its effects as a human carcinogenic agent, but few studies have dealt with neurobehavioral effects. In addition, studies of arsenic effects on development have only addressed its effects on embryotoxicity and teratogenicity after a single oral, gavage or intraperitoneal exposure. Among the behavioral alterations reported after intoxication with arsenic are both increased and decreased locomotor activity and learning deficits in a delayed alternation task [Toxicol. Lett. 54 (1990) 345; Bull. Environ. Contam. Toxicol. 50 (1993) 100; Brain Res. Bull. 55 (2001) 301]. To further characterize developmental and behavioral alterations induced by arsenic exposure, Sprague-Dawley rats were exposed to arsenite (36.70 mg arsenic/l in drinking water) from gestation day 15 (GD 15) or postnatal day 1 (PND 1), until approximately 4 months old. The pregnant or lactating dams received either the arsenic solution or regular drinking water and once pups were weaned, they continued receiving the same solution as drinking water. Animals exposed from GD 15 showed increased spontaneous locomotor activity and both exposed groups showed increased number of errors in a delayed alternation task in comparison to the control group. Total arsenic (TA) content in brain was similar for both exposed groups and significantly different from the control group. These results indicate that rats exposed to arsenic during development present deficits in spontaneous locomotor activity and alterations in a spatial learning task.
砷是一种环境污染物，在世界某些地区的土壤、水和空气中都有发现。它作为一种人类致癌物质的影响已得到广泛研究，但涉及神经行为影响的研究却很少。此外，关于砷对发育影响的研究仅涉及单次口服、灌胃或腹腔注射暴露后对胚胎毒性和致畸性的影响。在砷中毒后报告的行为改变中，既有运动活动增加和减少的情况，也有在延迟交替任务中出现学习缺陷的情况[《毒理学快报》54(1990)345；《环境污染物与毒理学通报》50(1993)100；《脑研究通报》55(2001)301]。为了进一步表征砷暴露引起的发育和行为改变，将斯普拉格-道利大鼠从妊娠第15天（GD 15）或出生后第1天（PND 1）开始暴露于亚砷酸盐（饮用水中含砷36.70毫克/升），直至约4个月大。怀孕或哺乳期的母鼠接受砷溶液或普通饮用水，幼崽断奶后，它们继续接受相同的溶液作为饮用水。从GD 15开始暴露的动物自发运动活动增加，与对照组相比，两个暴露组在延迟交替任务中的错误数量均增加。两个暴露组大脑中的总砷（TA）含量相似，且与对照组有显著差异。这些结果表明，在发育过程中暴露于砷的大鼠在自发运动活动方面存在缺陷，并且在空间学习任务中出现改变。
