Cetrorelix suppresses the preovulatory LH surge and ovulation induced by ovulation-inducing factor (OIF) present in llama seminal plasma
| dc.contributor.author | Silva, M. | |
| dc.contributor.author | Smulders, J. | |
| dc.contributor.author | Guerra, M. | |
| dc.contributor.author | Valderrama, X.P. | |
| dc.contributor.author | Letelier, C. | |
| dc.contributor.author | Adams, G.P. | |
| dc.date | 2011 | |
| dc.date.accessioned | 2012-02-07T21:46:17Z | |
| dc.date.available | 2012-02-07T21:46:17Z | |
| dc.date.issued | 2012-02-07 | |
| dc.description.abstract | Background: The purpose of the study was to determine if the effect of llama OIF on LH secretion is mediated by stimulation of the hypothalamus or pituitary gland.Methods: Using a 2-by-2 factorial design to examine the effects of OIF vs GnRH with or without a GnRH antagonist, llamas with a growing ovarian follicle greater than or equal to 8 mm were assigned randomly to four groups (n = 7 per group) and a) pre-treated with 1.5 mg of GnRH antagonist (cetrorelix acetate) followed by 1 mg of purified llama OIF, b) pre-treated with 1.5 mg of cetrorelix followed by 50 micrograms of GnRH, c) pre-treated with a placebo (2 ml of saline) followed by 1 mg of purified llama OIF or d) pre-treated with a placebo (2 ml of saline) followed by 50 micrograms of GnRH. Pre-treatment with cetrorelix or saline was given as a single slow intravenous dose 2 hours before intramuscular administration of either GnRH or OIF. Blood samples for LH measurement were taken every 15 minutes from 1.5 hours before to 8 hours after treatment. The ovaries were examined by ultrasonography to detect ovulation and CL formation. Blood samples for progesterone measurement were taken every-other-day from Day 0 (day of treatment) to Day 16.Results: Ovulation rate was not different (P = 0.89) between placebo+GnRH (86%) and placebo+OIF groups (100%); however, no ovulations were detected in llamas pre-treated with cetrorelix. Plasma LH concentrations surged (P < 0.01) after treatment in both placebo+OIF and placebo+GnRH groups, but not in the cetrorelix groups. Maximum plasma LH concentrations and CL diameter profiles did not differ between the placebo-treated groups, but plasma progesterone concentrations were higher (P < 0.05), on days 6, 8 and 12 after treatment, in the OIF- vs GnRH-treated group.Conclusion: Cetrorelix (GnRH antagonist) inhibited the preovulatory LH surge induced by OIF in llamas suggesting that LH secretion is modulated by a direct or indirect effect of OIF on GnRH neurons in the hypothalamus. © 2011 Silva et al; licensee BioMed Central Ltd. | es |
| dc.format | es | |
| dc.identifier.citation | Reproductive Biology and Endocrinology, Vol. 32, N°1, 77-84, 2011 | es |
| dc.identifier.doi | 10.1186/1477-7827-9-74 | es |
| dc.identifier.uri | https://repositoriodigital.uct.cl/handle/10925/584 | |
| dc.language.iso | en | es |
| dc.source | Reproductive Biology and Endocrinology | es |
| dc.subject | Factor ovulatorio | es |
| dc.subject | Cetrorelix | es |
| dc.subject | Camélidos | es |
| dc.title | Cetrorelix suppresses the preovulatory LH surge and ovulation induced by ovulation-inducing factor (OIF) present in llama seminal plasma | es |
| dc.type | Artículo de Revista | es |
| uct.carrera | Agronomía | es |
| uct.carrera | Ingeniería en Recursos Naturales Renovables | es |
| uct.carrera | Medicina Veterinaria | es |
| uct.catalogador | aga | es |
| uct.comunidad | Recursos Naturales | es |
| uct.facultad | Facultad de Recursos Naturales | es |
| uct.indizacion | ISI | es |