中文摘要：

目的：利用大鼠胚胎肢芽和中脑细胞微团培养模型研究染料木黄酮（genistein,GEN）的发育毒性,并探讨其发育毒性机制。方法：实验分为不同浓度的GEN（0、0.94、1.875、3.75、7.5、15.0μg/ml）染毒组,受试物分别作用于培养大鼠胚胎肢芽细胞和中脑细胞微团,采用中性红摄取法检测GEN对细胞增殖的影响,采用阿利新蓝染色方法检测GEN对肢芽细胞分化的影响,采用图像处理分析方法检测GEN对中脑细胞分化的影响。计算细胞50%增殖抑制浓度（IC50-P）和50%分化抑制浓度（IC50-D）。用不同浓度的雌激素受体拮抗剂ICI182780（0.1,0.5,1μmol/L）分别预处理细胞后再加入GEN（7.5μg/ml）,观察雌激素受体途径在GEN诱导的发育毒性中的作用。结果：GEN对肢芽细胞的IC5-0P和IC5-0D分别为5.4μg/ml和4.9μg/ml,GEN对中脑细胞的IC5-0P为6.2μg/ml,IC5-0D分别为7.1μg/ml（集落分化个数）或5.3μg/ml（集落分化面积）。IC5-0P/IC50-D的比值均接近1。在GEN7.5μg/ml染毒组,用ICI182780预处理细胞,不能改变GEN诱导的发育毒性作用。结论：根据Flint＇s和欧洲替代方法验证中心ECVAM致畸物判别标准,并结合人体实际可能接触水平,认为GEN为强致畸物,并且对人类存在可能的风险。其致畸作用可能主要通过细胞毒性发挥作用,不依赖于雌激素受体途径。

英文摘要：

OBJECTIVE：To explore the developmental toxicity of genistein（GEN）by micromass cultures of rats limb bud（LB）and midbrain（MB）cells,and investigate its possible mechanisms.METHODS：Micromass cultures of LB and MB were exposed to GEN with a series of concentrations（0,0.94,1.875,3.75,7.5 and 15 μg/ml）.The effect of GEN on cell proliferation was detected by neutral red uptake;the effect of GEN on LB and MB differentiation was assessed by Alcian Blue Staining and Image Analysis,respectively.Cell cultures were pretreated by ICI182780（0.1,0.5 and 1 μmol/L）,and then with GEN（7.5 μg/ml）added,in order to observe the role of estrogen receptor pathway in the developmental toxicity induced by GEN.RESULTS：For micromass cultures of LB,IC50-P（cell proliferation）and IC50-D（cell differentiation）of GEN were 5.4 μg/ml and 4.8 μg/ml,respectively.For micromass cultures of MB,they were 6.2 μg/ml and 7.1 μg/ml（differentiation judged by number of foci）/5.3 μg/ml（differentiation judged by area of foci）,respectively.The ratio IC50-P/IC50-D all approximated to 1.The developmental toxicity induced by GEN with 7.5 μg/ml could not be changed by ICI182780 pre-treatment.CONCLUSION：According to the discrimination rules of Flint and European Center for the Validation of Alternative Methods（ECVAM）,and in the light of the human exposure level,GEN was regarded as a strong teratogen,with potential risk toward human.The results indicated that the developmental toxicity GEN may not be mediated by estrogen receptor（ER）pathway.