Liu Jin, Huang Huiling, Zhang Wenchang, Li Hong
Department of Occupational and Environmental Health, University of Public Health, Fujian Medical University, Fuzhou, Fujian, P.R. China.
Birth Defects Res B Dev Reprod Toxicol. 2010 Feb;89(1):43-9. doi: 10.1002/bdrb.20233.
Cadmium (Cd) increases in uterine wet weight in rodents remain unclear and there are only a few studies that examined the effects of Cd on uterine morphology. It is unknown whether Cd induces a uterotrophic effect via its interaction with the estrogen receptor (ER). In our study, we compared the effects of cadmium chloride (CaCl(2)) on uterine wet weight and morphology to those of 17beta-estradiol in Sprague-Dawley (SD) rats.
Forty-eight SD rats (23 days of age) were ectomized and randomly divided into six groups (eight rats per group): vehicle control (sterile saline solution), positive control (17beta-estradiol, 0.03 mg/kg in peanut oil), and CaCl(2) groups (0.0064, 0.032, 0.16, and 0.8 mg/kg, respectively). The animals were treated by daily intraperitoneal (i.p.) injection for 3 days. The uteri were removed and assessed for weight, morphology, and immunohistochemical analysis.
Compared to the control group, the uterine wet weight, the thickness of endomerium, the thickness of the stroma and the nucleus/cytoplasm ratio in the 17beta-estradiol-treated and 0.8 mg/kg-day CaCl(2)-treated groups changed (P<0.01 or P 0.05). The endometrial gland number, the uterine epithelial cell height, and the PCNA-positive expression in 17beta-estradiol-treated rats increased compared to that of the control (P<0.01), but not in the CaCl(2) dose groups.
These results indicate that cadmium may induce an increase in uterine wet weight. However, this effect is not similar to that caused by 17beta-estradiol, suggesting it is not via Ca-ER interactions.
镉（Cd）增加啮齿动物子宫湿重的机制尚不清楚，仅有少数研究探讨了镉对子宫形态的影响。镉是否通过与雌激素受体（ER）相互作用诱导子宫营养效应尚不清楚。在本研究中，我们比较了氯化镉（CaCl₂）和17β-雌二醇对Sprague-Dawley（SD）大鼠子宫湿重和形态的影响。
48只23日龄的SD大鼠切除卵巢后随机分为6组（每组8只）：溶剂对照组（无菌生理盐水）、阳性对照组（17β-雌二醇，0.03mg/kg溶于花生油）和CaCl₂组（分别为0.0064、0.032、0.16和0.8mg/kg）。动物每天腹腔注射3天。取出子宫并评估其重量、形态和免疫组织化学分析。
与对照组相比，17β-雌二醇处理组和0.8mg/kg·天CaCl₂处理组的子宫湿重、子宫内膜厚度、基质厚度和核质比发生了变化（P<0.01或P<0.05）。与对照组相比，17β-雌二醇处理组大鼠的子宫内膜腺体数量、子宫上皮细胞高度和PCNA阳性表达增加（P<0.01），但CaCl₂剂量组未见增加。
这些结果表明镉可能诱导子宫湿重增加。然而这种作用与17β-雌二醇引起的作用不同，提示其不是通过Ca-ER相互作用。
