ABSTRACT
AIM: To investigate the apoptosis and Bcl-2/Bax expression in the early follicles of women at reproductive age. METHODS: 12 ovarian specimens were collected from reproductive women (aged 23-38 years) undergoing gynaecological operation. Histopathological examination of these specimens was performed to confirm its' morphological normalities. Using TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling) assay and immunohistochemistry method, cell apoptosis and Bcl-2/Bax expression were examined in the early follicles including mainly primordial, intermediary and primary follicles. RESULTS: 18.75% of the oocytes were found TUNEL positive in the early follicles, but no granulosa cells in these follicles were found TUNEL positive. Bax expression was detected in 76.07% of the oocytes in the early follicles, but Bcl-2 expression was negative in these oocytes. In addition, Bcl-2/Bax expression were not present in the granulosa cells in early follicles. CONCLUSION: The oocyte apoptosis occurs in the early follicles of reproductive woman, and pro-apoptotic protein Bax may play a role in regulating this process. It suggests that Bax mediated oocyte apoptosis may be the molecular mechanism of the early follicle atresia in the ovaries of reproductive woman. [