铬污染区地下水对大鼠肝脏功能及Caspase-3和PARP表达的影响*

Effect of chromium on liver function and expression of Caspase-3 and PARP in rats*

摘要:

目的 研究铬污染区地下水对大鼠肝功能、Caspase-3和聚腺苷二磷酸-核糖聚合酶（PARP）表达的影响。方法 将10只健康SD孕鼠随机分成空白组、地下水组、低铬组、中铬组及高铬组，每组2只。分别灌胃蒸馏水、铬含量为28.64?mg/L的铬污染区地下水，以及剂量为0.8、4.0和20.0?mg/kg的重铬酸钾溶液。21?d后小鼠断奶，按母鼠分组直接灌胃，灌胃剂量不变（0.5?ml/100?g），1次/d，连续灌胃21周。解剖子代大鼠后取血液及肝组织，用原子吸收光谱仪（石墨炉法）检测肝组织中的铬含量及血清中TP、ALB、GLB的含量，以及AST、ALT、ALP的活力，用苏木精-伊红（HE）染色法制作切片，观察肝脏的病理变化，并用免疫组织化学法检测Caspase-3和PARP的表达情况。结果 与空白组比较，地下水组与各剂量重铬酸钾染毒组肝脏中铬的含量均升高，且随着染毒剂量的升高，子代大鼠肝脏中铬含量呈上升趋势，差异有统计学意义（P?<0.05）。地下水组与各剂量重铬酸钾染毒组血清中TP、ALB、GLB的含量均升高，中铬组和高铬组与空白组间的差异有统计学意义（P?<0.05）。地下水组与各剂量重铬酸钾染毒组血清中的AST、ALT、ALP活力均高于空白组，各剂量重铬酸钾染毒组与空白组间的差异有统计学意义（P?<0.05）。HE染色结果显示地下水组与重铬酸钾染毒剂量组的肝细胞表现为不同程度的嗜酸性样变，排列紊乱，细胞质间隙加大及空泡性样变。免疫组织化学结果显示，地下水组Caspase-3和PARP阳性表达率与低铬组相仿，各剂量重铬酸钾染毒组随着重铬酸钾浓度升高，肝细胞阳性率升高。结论 六价铬长期暴露对大鼠的肝功能造成一定损伤，且使肝细胞Caspase-3和PARP表达增强。

Abstract:

Objective To study the effect of groundwater in chromium contaminated area on liver function and expression of Caspase-3 and PARP in rats. Methods Groundwater in chromium-contaminated areas was used as the experimental group, and potassium dichromate with different concentrations was used as the positive control group. Ten pregnant SD rats were randomly divided into 5 groups (n?=?2). The female rates after delivering were treated with distilled water, groundwater in a chromium-contaminated area (28.64?mg/L), and potassium dichromate solutions (0.8, 4, or 20?mg/kg). After weaning, offspring continuously receiving same treatment for 21 consecutive weeks on daily basis. Blood and liver tissue were harvested for measuring serum TP, ALB, GLB, AST, ALT, ALP content. The content of chromium in liver tissue was measured by atomic absorption spectrophotometer (graphite furnace method). HE staining was made for identification of pathological changes of liver. Expression of Caspase-3 and PARP were detected by immunohistochemical staining. Results Compared with the blank group, the content of chromium in the liver increased in dose dependent manner (P?