OBJECTIVE: To examine the effect of a gonadotropin-releasing hormone agonist (GnRH-a), leuprolide acetate (LA), on human chorionic gonadotropin/luteinizing hormone (LH) receptors content and progesterone (P) and estradiol (E2) production in cultured granulosa or luteal cells. DESIGN: Prospective. SETTING: Private Fertility Clinic and National Research Institute. PATIENTS: Twenty patients undergoing in vitro fertilization or gamete intrafallopian transfer programs. RESULTS: Human chorionic gonadotropin/LH receptors in human granulosa cells increased after 48 hours of culture, and LA inhibited such effect. Leuprolide acetate, 1 ng/mL, in the cultures produced an increase in P production. On the contrary, LA inhibited E2 production. Additionally, the in vivo effect of LA (2 micrograms/rat per 7 days) was studied in corpus luteum of superovulated rats. Luteal cells from LA-treated rats in culture produced lower P than the controls but showed an increase in aromatase activity. Luteal LH receptors declined after 48 hours of culture with LA. CONCLUSION: The high doses of gonadotropin necessary to induce ovarian hyperstimulation when GnRH-a is administered could be related with an inhibitory effect of these agonists on LH receptors and aromatase activity.
OBJECTIVE: To examine the effect of a gonadotropin-releasing hormone agonist (GnRH-a), leuprolide acetate (LA), on human chorionic gonadotropin/luteinizing hormone (LH) receptors content and progesterone (P) and estradiol (E2) production in cultured granulosa or luteal cells. DESIGN: Prospective. SETTING: Private Fertility Clinic and National Research Institute. PATIENTS: Twenty patients undergoing in vitro fertilization or gamete intrafallopian transfer programs. RESULTS:Human chorionic gonadotropin/LH receptors in human granulosa cells increased after 48 hours of culture, and LA inhibited such effect. Leuprolide acetate, 1 ng/mL, in the cultures produced an increase in P production. On the contrary, LA inhibited E2 production. Additionally, the in vivo effect of LA (2 micrograms/rat per 7 days) was studied in corpus luteum of superovulated rats. Luteal cells from LA-treated rats in culture produced lower P than the controls but showed an increase in aromatase activity. Luteal LH receptors declined after 48 hours of culture with LA. CONCLUSION: The high doses of gonadotropin necessary to induce ovarian hyperstimulation when GnRH-a is administered could be related with an inhibitory effect of these agonists on LH receptors and aromatase activity.
Authors: R Fabbri; E Porcu; A Pession; E Sereni; T Marsella; R Seracchioli; C Flamigni Journal: J Assist Reprod Genet Date: 1996-04 Impact factor: 3.412
Authors: Luiz Eduardo T Albuquerque; Leopoldo O Tso; Humberto Saconato; Maria Cecília R M Albuquerque; Cristiane R Macedo Journal: Cochrane Database Syst Rev Date: 2013-01-31