不同价态无机砷染毒对大鼠脏器GSH-Px活力的影响

Influence of different valence state arsenic on GSH-Px vitality changes in rats′ organs

目的比较不同价态和剂量的NaAsO2(iAs3+)和Na2HAsO4(iAs5+)染毒对大鼠脏器组织谷胱甘肽过氧化物酶(GSH-Px)活力的影响,探讨砷毒作用机制。方法选用Wistar大鼠70只,随机分为对照组(C),iAs3+低(AL)2、中(AM)、高(AH)剂量组,iAs5+低(BL)、中(BM)、高(BH)剂量组,共7个组。高、中、低染毒剂量为20.0mg/kg、6.67 mg/kg、2.33 mg/kg、。采用自由饮水法染毒,根据每组每周平均体重调整水中受试物的浓度,连续染毒90 d。处死动物,取肝、脑、肾,组织进行匀浆,用紫外分光光度法(λ=412 nm)测定肝、肾、脑中GSH-Px的活力。结果各组大鼠肝脏、脑和肾脏中GSH-Px活力不全相同(P<0.01),各实验组GSH-Px活性与正常对照组均不同(P<0.05);AH组低于AL组相应脏器中GSH-Px的活力(P<0.01);脑组织中BH组GSH-Px的活力低于BL组(P<0.01),iAs3+组和iAs5+组差别无统计学意义(P>0.05)。结论 iAs3+或iAs5+染毒后大鼠脏器中抗氧化酶活力均降低,破坏机体氧化与抗氧化系统的动态平衡,从而导致机体的脂质过氧化损伤。

Objective To compare the differences of glutathione peroxidase（GSH-Px） vitality between rats after be used NaAsO2 or Na2HAsO4,investigate mechanism of toxicity in vivo about arsenic.Methods Seventy rats were randomly separated into seven groups including control group（C）,low dose NaAsO2 poisoning group（AL）,middle dose NaAsO2 poisoning group（AM）,and high dose NaAsO2 poisoning group（AH）,low dose Na2HAsO4 poisoning group（BL）,middle dose Na2HAsO4 poisoning group（BM）,and high dose Na2HAsO4 poisoning group（BH）.The high,middle and low dose of both was 20.0 mg/kg,6.67 mg/kg and 2.22 mg/kg.After 90 days,the animals were sacrificed and a series of biochemical indices were detected in liver,kidney and brain.The vitalities of GSH-Px in liver,kidney and brain were measured and analyzed by spectrophotometric method（λ=412 nm）.Results There were differences between experimental groups and normal control（P0.01）.GSH-Px vitality of high-dose group was lower than the low-dose group in NaAsO2 groups（P0.05）.In brain,GSH-Px vitality of high-dose group was lower than the low-dose group in NaAsO2 groups（P0.01）,while there was no statistics difference between NaAsO2 groups and Na2HAsO4 groups（P0.05）.Conclusion GSH-Px vitality was step down in the rats after be used NaAsO2 or Na2HAsO4.Close attention should be pay to reciprocal transformation between sodium arsenite and natrium arsenicum.