Effects of benzo(a)pyrene exposure on killifish (Fundulus heteroclitus) aromatase activities and mRNA.
Effects of benzo(a)pyrene exposure on killifish (Fundulus heteroclitus) aromatase activities and mRNA.
复制标题
DOI：
10.1016/j.aquatox.2005.12.009
复制
发表时间：
2006-05
影响因子：
4.5
通讯作者：
Monali Patel;B. Scheffler;Lu Wang;K. Willett
中科院分区：
文献类型：
--
作者：
Monali Patel;B. Scheffler;Lu Wang;K. Willett
细胞色素P450芳香化酶（CYP 19）通过将雄激素转化为雌激素在类固醇体内平衡中起重要作用。为研究苯并（a）芘（BaP）对芳香化酶mRNA表达和酶活性的影响，将成年人的胃底暴露于1和10μg/L的BaP，胚胎暴露于10μ g/L的BaP。BaP的影响进行了检查的组织，性别和季节的成年人。从组成上讲，性别之间的CYP 19 A2 mRNA水平没有显著差异，但雌性动物的脑芳香化酶活性更高。与雄性相比，雌性对照组鳉鱼的性腺中的CYP 19 A1 mRNA多700倍。在两种性别的脑组织中，CYP 19 A2 mRNA是CYP 19 A1的100倍。在卵巢中，CYP 19 A1约为CYP 19 A2的30倍，而在睾丸中，CYP 19 A2相对较多。在胚胎中，CYP 19 A2的表达高出1.5倍。由于个体间变异性高，未观察到芳香化酶mRNA受性别、季节或年龄影响的BaP处理的显著效果。10μg/L苯并（a）芘可显著降低卵巢芳香化酶活性，但冬季暴露后雌性脑活性增加。这些研究结果表明，芳香化酶是一个潜在的目标破坏鱼类发育和生殖生理的苯并（a）芘。
Cytochrome P450 aromatase (CYP19) plays an important role in steroid homoeostasis by converting androgens to estrogens. To evaluate the effects of benzo(a)pyrene (BaP), a model carcinogenic PAH and AhR ligand, on aromatase mRNA expression and enzyme activity, adult Fundulus were exposed to water-borne BaP (1 and 10μg/L) for 15 days, and embryos were exposed to 10μg/L for 10 days. Effects of BaP were examined by tissue, gender, and season in adults. Constitutively, the sexes did not have significantly different CYP19A2 mRNA levels, however females had higher brain aromatase activity. Female control killifish had more than 700-fold more CYP19A1 mRNA in their gonads compared to males. Within brain tissue of both sexes, there was 100-fold more CYP19A2 mRNA compared to CYP19A1. In ovary, CYP19A1 predominated by approximately 30-fold over the CYP19A2, but in testis there was relatively more CYP19A2. In embryos there was ∼5-fold higher CYP19A2 expression. Due to high inter-individual variability, a significant effect of BaP treatment by gender, season or age was not observed for either aromatase mRNA. However, ovarian aromatase activity was significantly decreased by 10μg/L BaP, while female brain activity was increased following winter exposure. These findings suggest that the aromatase enzyme is a potential target for disruption of fish developmental and reproductive physiology by BaP.