汞或镉及其联合应用对去卵巢大鼠的雌激素样作用

目的探讨HgCl2和CdCl2对去卵巢大鼠的雌激素样作用及不同剂量CdCl2对HgCl2雌激素样作用的影响。方法 SD大鼠行双侧去卵巢手术制备模型,按照分组,每天ip给予生理盐水(去卵巢模型对照组),雌二醇0.08mg·kg-1(阳性对照组),HgCl20.04,0.20和1.00mg·kg-1;CdCl20.08,0.40和2.00mg·kg-1;以及HgCl2+CdCl2(0.04+0.08),(0.04+0.40)和(0.04+2.00)mg·kg-1组,连续3d。观察子宫增重作用、子宫内膜细胞有丝分裂指数(MI)和嗜银染色(Ag-NORs)颗粒数。结果与去卵巢模型对照组相比,HgCl21.00mg·kg-1组和CdCl22.00mg·kg-1组均能显著诱导去卵巢大鼠子宫增殖(P<0.05);HgCl20.04mg·kg-1能够明显提高CdCl20.08和2.00mg·kg-1组子宫脏器系数(P<0.05)。HgCl2和CdCl2组MI随着染毒剂量的增加而递增,且呈剂量-效应关系,除CdCl20.08mg·kg-1组外,其余各组与去卵巢模型对照组相比较,MI均有明显差异(P<0.05);与去卵巢模型对照组相比,HgCl20.04mg·kg-1能够提高CdCl20.08,0.40和2.00mg·kg-1组MI(P<0.05);HgCl21.00mg·kg-1和CdCl22.00mg·kg-1大鼠子宫内膜Ag-NORs颗粒数明显增高(P<0.05),HgCl20.04mg·kg-1能够明显提高CdCl20.08和2.00mg·kg-1组Ag-NORs颗粒数(P<0.05)。结论 HgCl21.00mg·kg-1和CdCl22.00mg·kg-1单独应用具有雌激素样活性;HgCl20.04mg·kg-1与不具有雌激素样活性的CdCl20.08mg·kg-1和0.40mg·kg-1联合应用表现出雌激素样作用。

Estrogen-like effect of mercury and chromium in ovariectomized rats

OBJECTIVE To discuss the estrogen-like activity of ovariectomized rats on mercuric chloride (HgCl₂) and cadmium chloride (CdCl₂), and to discuss estrogen-like effect of different doses of CdCl₂ on HgCl₂. METHODS Sixty-six adult female SD rats were randomly divided into 11 groups after ovariectomy such as normal control group, estradiol positive control group, HgCl₂ 0.04, 0.20 and 1.00 mg·kg^-1 groups, CdCl₂ 0.08, 0.40 and 2.00 mg·kg^-1 groups, and HgCl₂+CdCl₂(0.04+0.08), (0.04+0.40) and (0.04+2.00)mg·kg^-1 groups. The animals were ip given drugs once a day, for 3 d. Uterotrophic effect, mitotic index (MI) of endometrial cells, and number of Ag-NORs were observed. RESULTS Compared with normal control group, HgCl₂ 1.00 mg·kg^-1 and CdCl₂ 2.00 mg·kg^-1 groups could induce the increase of uterine weight (P<0.05); HgCl₂+CdCl₂(0.04+0.08) and (0.04+2.00)mg·kg^-1 could significantly increase the uterine weight (P<0.05). Compared with normal control group, except CdCl₂ 0.08 mg·kg^-1 group, MI of endometrial cells significantly increased in HgCl₂ and CdCl₂ groups in a dose-response manner (P<0.05). Compared with negative control group, HgCl₂ 0.04 mg·kg^-1 could significantly increase MI of endometrial cells exposed to various CdCl₂ doses(P<0.05). Compared with negative control group, HgCl₂ 1.00 mg·kg^-1 and CdCl₂ 2.00 mg·kg^-1 could increase Ag-NORs of uterus(P<0.05). HgCl₂ 0.04 mg·kg^-1 could significantly increase Ag-NORs of uterus exposed to CdCl₂ 0.08 and 2.00 mg·kg^-1(P<0.05). CONCLUSION HgCl₂ 1.00 mg·kg^-1 and CdCl₂ 2.00 mg·kg^-1 used alone have the estrogen-like activity. HgCl₂ 0.04 mg·kg^-1 can cause CdCl₂ 0.08 and 0.40 mg·kg^-1 that haven′t the estrogen-like activity to display this activity.