Study of thyroid hormone disruption by the environmental contaminant bde-99 in perinatal rats

Identifier:  TDX:1275

Handle: https://hdl.handle.net/20.500.11797/TDX1275

Authors:  Blanco Pérez, Jordi

Abstract:
The main human concern about the environmental pollutants polybrominated diphenyl ethers (PBDEs) are the rising concentrations accumulated in women. The aim of the present thesis is the study of the toxicity by maternal transference of BDE-99 in the offspring. Among highlights of the results, we found that exposure to BDE-99 during the gestational period produced a delayed ossification, slight hypertrophy of the heart, and enlargement of the liver in rat fetuses. A transplacental effect of BDE-99, evidenced by the activation of nuclear hormones receptors that induce the upregulation of P450 isoforms, was also found in fetal liver correlated with an increase of reactive oxygen substances. Maternal transference of BDE-99 also produced a delay in the spatial learning task and a significant dose-response anxiolytic effect when rat pups were weaned. It was also found that the serum levels of thyroid hormones decreased and signs of hepatoxicity were observed. These results indicate a clear signal of toxicity in rat offspring by BDE-99 at levels comparable to those found in humans.