Neonatal exposure to bisphenol A reduces the pool of primordial follicles in the rat ovary

We evaluated whether exposure to bisphenol A (BPA) disrupts neonatal follicle development in rats From postnatal day 1 (PND1) to PND7 pups received corn oil (control) diethylstilbestrol (DES20 20 mu g/kg-d DES0 2 0 2 mu g/kg-d) or BPA (BPA20 20 mg/kg-d BPA0 05 0 05 mg/kg-d) We examined follicular dynamics multioocyte follicles (MOFs) incidence proliferation and apoptosis rates expression of steroid receptors (ER alpha ER beta PR AR) and cyclin-dependent kinase inhibitor 1B (p27) in PND8 ovaries DES20 DES0 2 and BPA20-ovaries showed fewer primordial follicles and increased growing follicles DES20-ovaries exhibited increased incidence of MOFs Oocyte survival AR PR and apoptosis were not changed Primordial and recruited follicles from BPA20-ovaries showed higher p27 whereas ER beta and proliferation were both increased in recruited follicles ERa positive primary follicles Increased in BPA 20-ovaries Results show that BPA reduces the primordial follicle pool by stimulating the neonatal initial recruitment associated with an increased proliferation rate likely mediated by an estrogenic pathway (C) 2010 Elsevier Inc All rights reserved