Reproduction · 1974 · 33 citations · 5 references
Veterinary MedicineAnimal SciencesEndocrinologyParturitionReproductive EndocrinologyReproductive PhysiologyPituitary HormonesRuminant EndocrinologyRuminant Reproductive MedicineSheep PhysiologySheep ReproductionEwe Reproductive PhysiologyGestation PhysiologyGonadotropin-releasing Hormone RegulationPituitary Dysfunction
Summary. Synthetic gonadotrophin-releasing hormone (Gn-RH) was infused at 1·5 μg/hr for 5 hr into ewes at 6, 13 and 18 weeks of gestation, around the time of parturition and at 3 and 6 weeks post partum. Changes in the concentration of FSH in plasma were measured by radioimmunoassay. Pituitary response to Gn-RH decreased during gestation with no detectable release of ovine FSH by 18 weeks. There was a marginal response in two of three ewes treated around parturition. No response was observed in two ewes treated at 3 weeks but a slight response was observed in one of the two ewes treated at 6 weeks post partum. These findings suggest that the ovine pituitary is progressively depleted of FSH or becomes refractory to Gn-RH during pregnancy.
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Lois A. Salamonsen, Helen A. Jonas, Henry Burger et al. · Endocrinology · 1973 · 76 citations
Veterinary Medicine, Endocrinology, Reproductive Endocrinology +12