亚慢性铅镉联合暴露对大鼠肝功能的影响及α-硫辛酸的保护作用

The effect of the combined exposure of sub-chronic lead and cadmium on liver function of rats and the protection effect of α-lipoic acid

为了研究铅镉联合暴露对大鼠肝功能的影响以及α-硫辛酸的保护作用,试验以300 mg/L铅(Pb)、50 mg/L镉(Cd)单独或联合(Pb+Cd)采用自由饮水方式染毒SD大鼠,α-硫辛酸保护组在Pb、Cd自由饮水的同时按体重以50 mg/kgα-硫辛酸灌胃,12周后测定血清中丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、血清碱性磷酸酶(ALP)活性及总蛋白(TP)、白蛋白(ALB)的含量。结果表明:与对照组相比,铅组、镉组ALT活性极显著升高(P<0.01),AST和ALP活性极显著下降(P<0.01),镉组TP和ALB含量显著或极显著下降(P<0.05或P<0.01),铅组TP和ALB含量无显著性差异,铅镉联合组ALT和AST活性极显著升高(P<0.01),ALP活性、TP和ALB含量无显著性差异;与铅、镉单独染毒组相比,铅镉联合组ALT、AST活性极显著升高(P<0.01),ALP活性、TP和ALB含量无显著性差异;与相应染毒组相比,α-硫辛酸保护组大鼠肝功能各项指标均有所恢复,部分具有统计学意义(P<0.05)。说明铅、镉单独或联合暴露对大鼠肝功能有损伤作用,α-硫辛酸可在一定程度上降低铅、镉单独或联合引起的肝功能损伤。

To study the effect of the combined exposure of sub - chronic lead and cadmium on liver function of rats and the protection effect of α-lipoid - acid, SD rats were exposed to 300 mg/L of lead （Pb） and 50 mg/L of cadmium （Cd） alone or in combination by free drinking wa- ter. Meanwhile the rats in the α-lipoic acid - protected group were fed 50 mg/Kg · Bw of α-lipoid - acid by intragastric administration, and then the activities of serum alanine aminotransferase （ ALT）, aspartate aminotransferase （AST） and the contents of serum alkaline phosphatase （ ALP）, total protein （TP） and albumin （ ALB ） were determined after 12 weeks. The results showed that the activities of ALT were significant- ly increased （ P 〈 0.01 ） in the Pb - or Cd - treated groups compared with the control group, and the activities of AST and ALP were significant- ly decreased（ P 〈 0.01 ）in the Pb - or Cd- treated groups; the contents of TP and ALB were significantly decreased（ P 〈 0.05 ）or highly sig- nificantly decreased （ P 〈 0.01 ） in the Cd - treated group, but the contents of TP and ALB had no significance （ P 〉 0.05 ） in the Pb - treated group; the activities of ALT and AST were highly significantly increased significantly（ P 〈 0.01 ） in the Pb and Cd co- treated group, but the ALP activity and the contents of TP and ALB had no significances （ P 〉 0.05 ） in the Pb and Cd co - treated group. The activities of AST and ALP increased significantly（ P 〈 O. 01 ） in the Pb and Cd co - treated group compared with the Pb or Cd - treated groups, but the ALP activity and the contents of TP and ALB had no significances （ P 〉 0.05 ） in the Pb and Cd co - treated group ; The various indexes of liver function in the α-lipoic acid - protected group were recovered and some of them were statistically significant （ P 〈 0.05 ） compared with the correspond- ing exposure group. The results indicate that sub - chronic Pb and Cd alone or combined exposure has damage effect on the liver function of rats , while and α- lipoic acid can reduce the damage caused by Pb and Cd alone or combined exposure to some degree.