Reports demonstrated that the exposures of embryonic ovaries to the toxicants (polycyclic aromatic hydrocarbons) reduces oocytes' pools determining the ovarian lifespans. In our study, possible effects of an aromatic hydrocarbon, 4 (3H) quinazolinone-2- ethyl-2-phenyl ethyl (QEPE) on the ovaries of embryos of pregnant Balb/C mice treated with 100 mg/kg/body weight of QEPE intraperitoneally, were investigated. Histological studies demonstrated QEPE reduces the number of healthy oocytes and TUNEL assay analysis indicated that this reduction was correlated to an increase in the number of apoptotic oocytes. Furthermore, electron microscopic (TEM) observations confirmed apoptotic cells mentioned above, and RT-PCR analysis showed QEPE would increase levels of Bax and Caspase-2 (two important proapoptotic genes)mRNAs in ovaries of the embryos of Balb/C mice treated with QEPE. In conclusions, QEPE induces apoptosis in the mouse fetal oocytes via a mechanism involved in increasing Bax and Caspase2 expressions.
- Embryonic ovary