采用HPLC和斑马鱼胚胎发育方法,测定了己烯雌酚(DES)在标准模式种斑马鱼胚胎体内的蓄积规律及胚胎毒性效应,并利用定量活性-结构分析(QSAR)和基因芯片技术,探讨了DES对斑马鱼胚胎的致毒机制.结果表明,在0.2mg/LDES中暴露24、48和72h后,胚胎体内的DES含量分别为(25.78±4.95)、(54.88±7.10)和(71.93±10.55)μg/g;不同起始染毒时间(0hpf和8hpf)条件下,亚致死最敏感指标均为72h孵化率抑制,EC50分别为(0.14±0.09)和(0.33±0.14)mg/L,说明胚胎在发育囊胚期(发育8h)前对DES暴露更为敏感.QSAR研究发现,DES相对其它酚类类雌激素对斑马鱼胚胎具有较高的毒性,这与它具有较高的TE值(51.1217eV)相关;基因芯片研究发现,5μg/LDES暴露21d后能导致斑马鱼成鱼部分基因表达异常.DES对斑马鱼具有一定的胚胎毒性和遗传毒性,而生化反应是致毒的关键步骤.
The bioaccumulation regulation and the toxicity of diethylstilbestrol (DES) were studied on zebrafish (Danio rerio ) embryos with the methods of HPLC and early life stage test, and the toxic mechanisms were also discussed with the techniques of quantitative structure-activity relationship (QSAR) and gene chips. After the zebrafish embryos exposed at 0.2 mg· L^-1 DES for 24, 48 and 72 h, the body levels of DES in zebrafish embryo were (25.78 ± 4.95), (54.88 ± 7.10) and (71.93 ± 10.55) μg/g, respectively. Even exposure started at different time (0 hpf and 8 hpf), the most sensitive sub lethal endpoints were both 72 h delayed hatch, and the ECs0 values for them were (0.14 ± 0.09) and (0.33± 0.14) mg/L, so that zebrafish embryo was more sensitive to the exposure of DES before the stage of gastrula (8 h after fertilization). QSAR studies found when compared with other phenol-endocrine disrupts, DES was much more toxic, and this related to its higher TE value (52.1217 eV). Meanwhile, when adult zebrafish exposed at 5 μg/L DES for 21 d, it was found by the gene chips that parts of gene expressions would be changed and the genetic toxicity of DES was approved. DES was concluded to be developmental and genetic toxic to zebrafish, and the biochemical reaction-associated process might be the key parameter in determining the toxicity level.