Effects of Estrogen and Bisphenol-A Exposure During Adolescent Development: A Golgi Study

Exposure to Bisphenol A (BPA) is inevitable because it is found in compounds we are exposed to daily, such as plastics, epoxy, and flame retardant materials. BPA is a known endocrine disruptor that interacts with estrogen and can affect both neuronal development and behavior. Previous studies, done on adult rats, have demonstrated that estrogen increases and BPA decreases spine density in the hippocampus. In the present study we investigated the effects of BPA administration during adolescence on spine density in the hippocampus of female rats at two time points. Female ovariectomized rats (6/group) were injected with BPA, estrogen, or oil during adolescence (postnatal days 42-49) and sacrificed at day 49 (Group 1) or day 79 (Group 2). Brains were removed and processed for Golgi impregnation and dendritic spine density was assessed in CA1 pyramidal cells and granule cells of the hippocampus. Given that adolescent brains are still developing and more vulnerable to outside stimuli, we hypothesize that BPA will have profound effects on dendritic spine density in the hippocampus. In addition the results of the present study will allow for a direct comparison of BPA and estrogen effects on dendritic spine density in adolescent and adult brains.