title: Kisspeptin synchronizes preovulatory surges in cyclical ewes and causes ovulation in seasonally acyclic ewes.
abstract: We determined whether kisspeptin could be used to manipulate the gonadotropin axis and ovulation in sheep. First, a series of experiments was performed to determine the gonadotropic responses to different modes and doses of kisspeptin administration during the anestrous season using estradiol-treated ovariectomized ewes. We found that: 1) injections (iv) of doses as low as 6 nmol human C-terminal Kiss1 decapeptide elevate plasma LH and FSH levels, 2) murine C-terminal Kiss1 decapeptide was equipotent to human C-terminal Kiss1 decapeptide in terms of the release of LH or FSH, and 3) constant iv infusion of kisspeptin induced a sustained release of LH and FSH over a number of hours. During the breeding season and in progesterone-synchronized cyclical ewes, constant iv infusion of murine C-terminal Kiss1 decapeptide-10 (0.48 mumol/h over 8 h) was administered 30 h after withdrawal of a progesterone priming period, and surge responses in LH occurred within 2 h. Thus, the treatment synchronized preovulatory LH surges, whereas the surges in vehicle-infused controls were later and more widely dispersed. During the anestrous season, we conducted experiments to determine whether kisspeptin treatment could cause ovulation. Infusion (iv) of 12.4 nmol/h kisspeptin for either 30 or 48 h caused ovulation in more than 80% of kisspeptin-treated animals, whereas less than 20% of control animals ovulated. Our results indicate that systemic delivery of kisspeptin provides new strategies for the manipulation of the gonadotropin secretion and can cause ovulation in noncyclical females.
authors: Unité Mixte de Recherche 6175, Physiologie de la Reproduction et des Comportements (Institut National de la Recherche Agronomique/Centre National de la Recherche Scientifique/Université Tours/Haras Nationaux), 37380, Nouzilly, France. caraty@tours.inra.fr
authors: A
authors: A
authors: Caraty
authors: J T
authors: JT
authors: Smith
authors: D
authors: D
authors: Lomet
authors: S
authors: S
authors: Ben Saïd
authors: A
authors: A
authors: Morrissey
authors: J
authors: J
authors: Cognie
authors: B
authors: B
authors: Doughton
authors: G
authors: G
authors: Baril
authors: C
authors: C
authors: Briant
authors: I J
authors: IJ
authors: Clarke
mesh_terms: D000818:Animals; D004305:Dose-Response Relationship, Drug; D030762:Estrous Cycle / Q000097:blood / Q000187:drug effects*; D005260:Female; D005498:Follicular Phase / Q000097:blood / Q000187:drug effects*; D007987:Gonadotropin-Releasing Hormone / Q000134:cerebrospinal fluid; D006062:Gonadotropins / Q000097:blood*; D006801:Humans; D059648:Kisspeptins; D051379:Mice; D009842:Oligopeptides / Q000494:pharmacology*; D010060:Ovulation / Q000097:blood / Q000187:drug effects*; D010062:Ovulation Induction / Q000379:methods / Q000662:veterinary; D012098:Reproduction / Q000187:drug effects; D012621:Seasons; D012756:Sheep
chemical_list: D006062:Gonadotropins; C106628:KISS1 protein, human; D059648:Kisspeptins; D009842:Oligopeptides; D007987:Gonadotropin-Releasing Hormone