Vega-López Armando, Jiménez-Orozco F Alejandro, Ramón-Gallegos Eva, García-Latorre Ethel, Domínguez-López M Lilia
Laboratorio de Toxicología Ambiental, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Unidad Profesional Adolfo López Mateos Zacatenco, Del. Gustavo A. Madero, México, Distrito Federal, CP 07738, México.
Environ Toxicol Chem. 2008 Apr;27(4):963-9. doi: 10.1897/07-446.1.
The present study examines the relationships between cytochrome P4501A (CYP1A) activity and vitellogenin (VTG) induction in Ameca splendens elicited by a polychlorinated biphenyl (PCB) mixture. Ethoxyresorufin-O-deethylase (EROD) activity, mRNA levels of VTG, and VTG induction were evaluated in male and female fish exposed for 1, 2, 4, 8, and 16 d to a commercial PCB mixture. Polychlorinated biphenyls induced higher EROD in both sexes and this induction was higher in females than in males. Maximum EROD and VTG induction occurred on day 1 in females, while in males these maxima occurred on days 8 and 16. A correlation between EROD and VTG induction was found only in males (p<0.001), and VTG induction was also higher in males than in females (p<0.01). Exposure to PCBs elicited increases in VTG expression and induction over time in males, while in females these decreased at the end of the exposure period. Deficiencies in the feedback mechanisms of male A. splendens exposed in the wild to xenoestrogens such as PCBs have probably contributed to alter the sex ratio of wild populations of this species.
本研究考察了多氯联苯（PCB）混合物引发的阿氏亮丽鲞中细胞色素P4501A（CYP1A）活性与卵黄蛋白原（VTG）诱导之间的关系。对暴露于商用PCB混合物1、2、4、8和16天的雄性和雌性鱼类，评估了乙氧基异吩恶唑酮 - O - 脱乙基酶（EROD）活性、VTG的mRNA水平以及VTG诱导情况。多氯联苯在两性中均诱导出较高的EROD，且雌性中的诱导水平高于雄性。雌性在第1天出现最大EROD和VTG诱导，而雄性在第8天和第16天出现这些最大值。仅在雄性中发现EROD与VTG诱导之间存在相关性（p<0.001），并且雄性中的VTG诱导也高于雌性（p<0.01）。暴露于多氯联苯使雄性中VTG表达和诱导随时间增加，而雌性在暴露期结束时这些指标下降。野生环境中暴露于多氯联苯等外源性雌激素的雄性阿氏亮丽鲞反馈机制的缺陷可能导致了该物种野生种群性别比例的改变。
