Polycyclic aromatic hydrocarbons (PAHs) are an important group of environmental pollutants, known for their mutagenic and carcinogenic activities. Many PAHs are aryl hydrocarbon receptor (AhR) ligands and several recent studies have suggested that PAHs or their metabolites may activate estrogen receptors (ER). The present study investigated possible estrogenic/antiestrogenic effects of abundant environmental contaminants benzo[a]pyrene (BaP), benz[a]anthracene (BaA), fluoranthene (Fla) and benzo[k]fluoranthene (BkF) in vivo, using the immature rat uterotrophic assay. The present results suggest that BaA, BaP and Fla behaved as estrogen-like compounds in immature Wistar rats, when applied for 3 consecutive days at 10mg/kg/day, as documented by a significant increase of uterine weight and hypertrophy of luminal epithelium. These effects were likely to be mediated by ERalpha, a major subtype of ER present in uterus, as they were inhibited by treatment with ER antagonist ICI 182,780. BaA, the most potent of studied PAHs, induced a significant estrogenic effect within a concentration range 0.1-50mg/kg/day; however, it did not reach the maximum level induced by reference estrogens. The proposed antiestrogenicity of the potent AhR agonist BkF was not confirmed in the present in vivo study; the exposure to BkF did not significantly affect the uterine weight, although a weak suppression of ERalpha immunostaining was observed in luminal and glandular epithelium, possibly related to its AhR-mediated activity. The PAHs under study did not induce marked genotoxic damage in uterine tissues, as documented by the lack of Ser-15-phoshorylated p53 protein staining. With the exception of Fla, all three remaining compounds increased CYP1-dependent monooxygenation activities in liver at the doses used, suggesting that the potential tissue-specific antiestrogenic effects of PAHs mediated by metabolization of 17beta-estradiol also cannot be excluded. Taken together, these environmentally relevant PAHs induced estrogenic effects in vivo, which might affect their toxic impact and carcinogenicity.

• MeSH
• alfa receptor estrogenů metabolismus   MeSH
• cytochrom P-450 CYP1A1 metabolismus   MeSH
• endokrinní disruptory toxicita   MeSH
• epitel účinky léků   MeSH
• estradiol metabolismus   MeSH
• estrogeny biosyntéza   MeSH
• financování organizované MeSH
• fosforylace MeSH
• hydroxylace MeSH
• imunohistochemie MeSH
• jaterní mikrozomy metabolismus   účinky léků   MeSH
• krysa rodu rattus MeSH
• látky znečišťující životní prostředí toxicita   MeSH
• nádorový supresorový protein p53 metabolismus   MeSH
• ovarium účinky léků   MeSH
• polycyklické aromatické uhlovodíky toxicita   MeSH
• potkani Wistar MeSH
• uterus metabolismus   účinky léků   MeSH
• velikost orgánu účinky léků   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• ženské pohlaví MeSH
• zvířata MeSH