Effects of GnRH agonist on follicular granulosa cell apoptosis of rats

Gonadotropin-releasing hormone (GnRH) has been found to be expressed in ovaries in addition to hypothalamus to modulate cell differentiation and induces atretic follicles. Since the death of granulosa cells during the process of follicular atresia occurs by apoptosis phenomenon, in this study, we investigated the occurrence of apoptosis of granulosa cells of rat ovarian follicles under the influence of Buserelin acetate, a GnRH agonist. In this experimental case-control study, twelve 25-day-old female Wistar rats were randomly divided into 2 groups. The study and control groups received 0.2 mg/kg/d Buserelin acetate and normal saline, respectively, for 4 days. 24 hours after the last injection, the rats were anesthetized with a lethal dose of chloroform and ovaries were removed. Specimens were fixed in 10% formalin. After the passage, five-micron sections were prepared using a rotary microtome. Measurement of apoptosis was performed using a calibrated light microscope after TUNEL POD staining. Data were analyzed in GraphPad InStat software using independent t-test. P ≤ 0/05 was statistically considered significant. These data showed the average percentage of apoptotic cells in the control group 2/14 ± 0/52, and in the experimental group 3/75 ± 1/71. This difference was statistically significant (p≤0.0001). These findings suggest that Buserelin acetate increases apoptosis in the granulosa cells of ovarian follicles.