The effect of pre-treatment with a gonadotrophin-releasing hormone agonist on reproductive functions in mature cycling rats.
In order to investigate the performance of follicles in a rat model in which gonadotrophin-releasing hormone agonist (GnRHa) was used for hypothalamic-pituitary-ovarian axis suppression, three groups of mature cycling rats were studied. One group was treated with buserelin followed by pregnant mare's serum gonadotrophin (PMSG), and the second group was treated with PMSG alone. Both these hormonally treated groups received human chorionic gonadotropin for induction of ovulation. The third group received no hormonal treatment. The average number of ovulated oocytes recovered from rat oviducts pre-treated with GnRHa was significantly higher than that in rats treated with the gonadotrophin alone, in spite of the larger number of pre-ovulatory follicles present in the gonadotrophin-treated group. The morphology of both the pre-ovulatory and the post-ovulatory cumulus-oocyte complexes in the three groups appeared similar. No difference in the capacity of follicles of the three groups to synthesize progesterone in vitro in response to luteinizing hormone could be observed. We conclude that ovarian morphology and function are not impaired by pre-treatment with buserelin.
Raziel
A
A
Department of Obstetrics and Gynaecology, Assaf Harofeh Medical Centre, Zerifin, Israel.
Ron-el
R
R
Dekel
N
N
D000818:Animals; D002064:Buserelin / Q000494:pharmacology*; D005260:Female; D006064:Gonadotropins, Equine / Q000494:pharmacology; D007986:Luteinizing Hormone / Q000494:pharmacology; D009865:Oocytes / Q000166:cytology; D006080:Ovarian Follicle / Q000187:drug effects / Q000502:physiology; D010053:Ovary / Q000187:drug effects / Q000502:physiology*; D010062:Ovulation Induction; D011374:Progesterone / Q000096:biosynthesis; D051381:Rats; D017208:Rats, Wistar
D006064:Gonadotropins, Equine; D011374:Progesterone; D007986:Luteinizing Hormone; D002064:Buserelin