RESUMO
Perfluorooctane sulfonate (PFOS) is an endocrine disruptor highly persistent, bioaccumulative and neurotoxic, whose presence has been detected in different compartments of the environment. The aim of this study was to investigate whether PFOS could alter the HPA axis activity by modifying the gene and protein expression of corticotropin-releasing factor 1 receptor (CRF1r) and glucocorticoid receptor (Gr). For that purpose, Sprague-Dawley adult male rats were orally treated by gavage with 0.5; 1.0; 3.0 and 6.0â¯mg of PFOS/kg/day for 28 consecutive days. After PFOS administration, gene and protein expression of CRF1r were analysed in the hypothalamus, hippocampus, pituitary and adrenal glands. Moreover, Gr gene and protein expression were measured in hypothalamus, pituitary gland, prefrontal cortex, amygdala and hippocampus. The reported results indicate that (1) PFOS could inhibit HPA axis activity by diminishing gene and protein expression of CRF1r in the pituitary gland; (2) PFOS inhibits Gr protein expression in both prefrontal cortex and amygdala, which could be related to the toxic effects of this contaminant in this neuroendocrine axis and finally, (3) PFOS-treated rats would try to maintain the physiological levels of corticosterone by reducing the protein expression of Gr in the pituitary gland.
