Development of corpus luteum susceptibility to an analog of prostaglandin F2α, throughout the luteal phase in llamas (Lama glama)
Autor: | Carolina Paula Bianchi, M.A. Benavente, MV Cavilla, Marcelo A. Aba, E. Jorgensen |
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Rok vydání: | 2011 |
Předmět: |
endocrine system
medicine.medical_specialty media_common.quotation_subject Prostaglandin Luteal phase Luteal Phase Dinoprost chemistry.chemical_compound Endocrinology Food Animals Corpus Luteum Internal medicine Luteolysis medicine biology.domesticated_animal Animals Ovulation Progesterone media_common Ovulatory follicle biology Cloprostenol General Medicine Lama glama medicine.anatomical_structure chemistry Animal Science and Zoology Plasma progesterone Female Corpus luteum Camelids New World hormones hormone substitutes and hormone antagonists |
Zdroj: | Animal reproduction science. 131(3-4) |
ISSN: | 1873-2232 |
Popis: | The aim of the present study was to evaluate the susceptibility of the corpus luteum to d-cloprostenol (synthetic analog of PGF 2α ) throughout the luteal phase in llamas. Female llamas ( n = 43) were induced to ovulate by GnRH injection in the presence of an ovulatory follicle and randomly assigned into one of six groups: control and treated with an injection of d-cloprostenol on Day 3, 4, 5, 6 or 8 post GnRH. Blood samples were collected to determine plasma progesterone concentrations. There was no effect of treatment on animals injected on Day 3 or 4 post-GnRH. In animals treated on Day 5, different responses were observed. No effect of treatment was recorded in 27% of the animals whereas 55% of the llamas showed a transitory decrease followed by a recovery in plasma progesterone concentrations after d-cloprostenol injection, indicative of a resurgence of the corpus luteum, extending the luteal phase a day more than in control animals. In the remaining 18% of the animals injected on Day 5, (corresponding to those exhibiting the greatest plasma progesterone concentrations at the day of injection), complete luteolysis was observed. Plasma progesterone concentrations decreased to below 1 ng ml −1 24 h after d-cloprostenol in llamas injected on Day 6 or 8 post-GnRH. In conclusion, the corpus luteum of llamas is completely refractory to PGF 2α until Day 4 after induction of ovulation, being partially sensitive by Day 5 and fully responsive to PGF 2α , by Day 6 after induction of ovulation. |
Databáze: | OpenAIRE |
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