Objective: There is growing evidence that suggests a direct action of gonadotropin-releasing hormone agonist (GnRH-a) on endometrial growth. Consequently, our purpose was to evaluate the effect of GnRH-a on in vitro eutopic endometrial cell growth and apoptosis.
Design: Prospective study.
Setting: Research institute and clinical fertility center.
Patient(s): Sixteen women with untreated endometriosis and 14 controls.
Intervention(s): Biopsy specimens of eutopic endometrium were obtained from all subjects. Apoptosis and cell proliferation were examined in epithelial endometrial cell cultures after incubation with leuprolide acetate (LA), antide, and a combination of both.
Main outcome measure(s): The percentage of apoptotic cells was evaluated by the acridine orange-ethidium bromide technique; cell proliferation was assessed by (3)H-thymidine incorporation.
Result(s): Leuprolide acetate (LA) (100 ng/mL) enhanced apoptosis in endometrial cultures from patients with endometriosis and controls, and this effect was reversed by antide 10(-7)M. Cell proliferation was down-regulated by LA at 1, 10, and 100 ng/mL in cultures from women without and with endometriosis. The addition of antide 10(-7)M reversed this inhibition.
Conclusion(s): GnRH-a appears to have a direct effect by enhancing the apoptotic index and decreasing the cell proliferation in endometrial cells.