Bisphenol A exposure at puberty disrupts expression of the oestrogen receptor-alpha in the hypothalamus of male and female mice

Bisphenol A is a xenoestrogen that interacts with both of the oestrogen receptors, oestrogen receptor alpha (ERα) and oestrogen receptor beta (ERβ). At environmentally low doses, bisphenol A has been reported to influence behaviour and affect development of the brain and reproductive tissues in rodents. In the present study mice were treated daily with a low (50 µg/kg) oral dose of bisphenol A starting on postnatal day (PND) 32 until sacrifice (PND50 or PND100), and at autopsy brain, testis, and uterus of all animals were harvested for analysis. Immunohistochemistry was used to evaluate the changes in the number of cells expressing ERα in the arcuate nucleus and ventromedial nucleus of the hypothalamus. Histological evaluations were performed on the testis and uterus, while analysis of estradiol and testosterone was carried out on mouse serum. At PND50, bisphenol A exposure increased ERï�¡ expressing neurons in the arcuate nucleus and ventromedial nucleus of the hypothalamus of both male and female mice (p