title: Effects of growth hormone and gonadotrophin releasing hormone antagonists on ovarian follicle growth in sheep.
abstract: Our objective was to determine the effects of the administration of growth hormone (GH) alone or plus teverelix, a gonadotrophin releasing hormone antagonist (GnRHa), on follicle development in sheep. Ewes were treated daily for 6 days by the intramuscular route with 15 mg of GH alone (GH group; n = 6) or combined with two subcutaneous doses of GnRHa (1.5 mg) on days 0 and 3 of GH treatment (GH/GnRHa group; n = 6); the control group (n = 6) received similar treatment with saline solution. Plasma follicle stimulating hormone levels were significantly lower in the GH/GnRHa group than in the control (P < 0.001) and GH groups (P < 0.05). The number of follicles > or =2 mm increased to reach significant differences with control (18.7 +/- 0.6) on day 4 in GH/GnRHa group (22.7 +/- 0.5, P < 0.001) and on day 5 in GH group (20.3 +/- 0.4 vs. 17.0 +/- 0.6, P < 0.05). These results indicate that GH and GnRHa may be useful for increasing the number of gonadotrophin-responsive follicles in the ovary. However, follicle function could be affected as both GH and GH/GnRHa groups showed lower plasma inhibin A concentrations than control sheep (90-110 pg/mL vs. 170-185 pg/mL, P < 0.005).
authors.affiliation: Cátedra de Farmacología, Facultad de Veterinaria, UCM, Madrid, Spain.
authors.forename: P
authors.initials: P
authors.lastname: Gonzalez Añover
authors.forename: A
authors.initials: A
authors.lastname: Gonzalez-Bulnes
authors.forename: A
authors.initials: A
authors.lastname: Veiga-Lopez
authors.forename: R M
authors.initials: RM
authors.lastname: Garcia-Garcia
authors.forename: A S
authors.initials: AS
authors.lastname: McNeilly
authors.forename: T
authors.initials: T
authors.lastname: Encinas
mesh_terms: D000818:Animals; D004347:Drug Interactions; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000037:antagonists & inhibitors*; D013006:Growth Hormone / Q000494:pharmacology*; D006727:Hormone Antagonists / Q000494:pharmacology*; D009842:Oligopeptides / Q000494:pharmacology*; D006080:Ovarian Follicle / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000254:growth & development; D012756:Sheep; D014463:Ultrasonography
chemical_list: D006727:Hormone Antagonists; D009842:Oligopeptides; D007987:Gonadotropin-Releasing Hormone; D013006:Growth Hormone; C084350:antarelix