中文摘要：

目的分析亚砷酸钠和砷酸钠染毒对大鼠二氢尿嘧啶脱氢酶（NAD）含量的影响,寻找不同价态砷代谢的差异,为进一步阐明砷毒作用机制提供依据。方法 70只Wistar大鼠随机分成7组,第1组为正常对照组,饮用去离子水;第2～4组为染毒三价砷（iAS3＋）的高、中、低剂量组,分别给予20.0、6.7、2.2mg/kg体质量亚砷酸钠溶液;第5～7组为染毒五价砷（iAS5＋）高、中、低剂量组,分别给予20.0、6.7、2.2mg/kg体质量砷酸钠溶液。各组大鼠于染毒第3个月末处死,采集血样,并应用酶联免疫分析法（ELISA）测定大鼠血清NAD含量的变化。结果与对照组比较,砷酸钠高剂量组的NAD含量低于对照组（P〈0.05）,其余各组与对照组比较差异均无统计学意义。亚砷酸钠各剂量组间比较,高、中剂量组NAD含量均低于低剂量组（P〈0.05）。砷酸钠各剂量组间比较,高剂量组的NAD含量均低于中剂量组和低剂量组（P〈0.05）。亚砷酸钠和砷酸钠对应剂量组比较,亚砷酸钠高剂量组的NAD含量高于砷酸钠高剂量组（P〈0.05）,而亚砷酸钠中剂量组的NAD含量低于砷酸钠中剂量组（P〈0.05）。结论砷酸钠在高、中剂量染毒条件下分别表现为对NAD活性的抑制和促进,而亚砷酸钠对NAD活性的影响不明显,对NAD活性的影响不同可能与砷酸钠和亚砷酸钠在体内氧化还原代谢过程不同有关。

英文摘要：

Objective To explore the mechanism of arsenic toxicology furtherly and seek for the difference between sodium arsenite and sodium arsenate（different valence state arsenic）,we studied the influence on content of dihydrouracil dehydrogenas（NAD）in rats treated with sodium arsenite and sodium arsenate.Methods 70 Wistar rats were divided randomly into seven groups,10 rats for each group.Such as control group;sodium arsenite high dose group,middle dose group,low dose group administrated with different concentrations of sodium arsenite：20.0,6.7,2.2 mg/kg BW every the day;and sodium arsenate high dose group,middle dose group,low dose group administrated with different concentrations of sodium Arsenate：20.0,6.7,2.2 mg As/kg BW every the day.Animals were sacrificed three months later by cervical dislocation to collect the blood,the content of NAD in blood serum was detected by ELISA.Results Comparing the content between control group and sodium arsenate high dose group,the difference was statistically significant（P0.05）.Comparing the other groups with control group were not statistically significant.For sodium arsenites,the NAD content in the high dose group and middle dose group were significantly lower than the low dose group（P0.05）.but for sodium arsenates,the NAD content in the high dose group was significantly lower than that in the middle dose group and low dose group（P0.05）.Comparing the matched doses group of sodium arsenate and sodium arsenite,the NAD content of sodium arsenite in the high dose group was significantly higher than sodium arsenate＇（P0.05）,but the NAD content of sodium arsenite in the middle dose group was significantly lower than sodium arsenate＇（P0.05）.Conclusions Sodium arsenate with the high dose could inhibited NAD activity,but of the middle dose could promote NAD activity.sodium arsenite did not affect NAD significantly.So,metabolic pathway of sodium arsenate and sodium arsenite may be different in vivo.