dinoprost has been researched along with lutrelin-acetate* in 2 studies
2 other study(ies) available for dinoprost and lutrelin-acetate
Article | Year |
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Progesterone ensures full-length luteal phases during the breeding season in ewes.
To test the hypothesis that each luteal-phase increase in the serum concentration of progesterone throughout the breeding season prevents a short luteal phase in the next cycle, 22 ewes were treated with an i.v. injection of 10 micrograms gonadotrophin-releasing hormone (GnRH) agonist every 12 h for 33 days beginning on day 12 of a cycle synchronized with prostaglandin F2 alpha. Six days after the last injection of GnRH agonist, ten of the ewes were treated s.c. for 14 days with progesterone-containing silicone elastomer implants to generate luteal-phase serum concentrations. Twenty ewes stopped cycling during GnRH agonist treatment and 16 of these, eight controls and eight treated with progesterone, resumed cycling after the end of treatment. In the control ewes, oestrous cycles began 25.0 +/- 7.5 (S.E.M.) days after the end of GnRH agonist administration, a short luteal phase preceding initiation of cycles in six ewes. In contrast, all eight progesterone-treated ewes resumed cycling synchronously 22.0 +/- 0.2 days after the end of GnRH agonist treatment and all began with full-length luteal phases. These results support the hypothesis that each luteal-phase increment in the serum concentration of progesterone throughout the breeding season prevents a short luteal phase in the next cycle. Topics: Animals; Dinoprost; Female; Gonadotropin-Releasing Hormone; Luteal Phase; Progesterone; Sheep | 1991 |
Cyclic response of hypophysectomized rats to ovulation induced by LHRH agonist: mediation by prostaglandins.
Further confirmation that the LHRH/LHRH agonist-induced ovulation in the hypophysectomized (hypx) rat is due to a direct ovarian effect and not mediated by LH release from residual pituitary tissue or other CNS sites is provided by the persistence of this effect despite concomitant median eminence lesion or passive immunization to LH. Adrenalectomy did not affect the ovulatory activity of the LHRH agonist, D-Trp6-N alpha MeLeu7-DesGly10-Pro9-NHEt-LHRH (Wy-40,972), in the hypx rat. Prior administration of a potent LHRH antagonist blocked ovulation induced in hypx proestrous rats by Wy-40,972 but not by LH-S19. Ovulation can be induced by Wy-40,972 one day earlier (e.g. metestrus) in the intact rat than it can in the hypx rat. Results in the hypx metestrous rat indicate that the ovulatory responsiveness of the intact rat at this stage of the cycle may occur by complementary action of Wy-40,972-stimulated endogenous LH release and a direct ovarian effect of the agonist. Prostaglandins (PG) are involved in the ovulatory mechanism of Wy-40,972 in the hypx proestrous rat as evidenced by the dose-dependent inhibition of this effect by PG synthetase inhibitors, indomethacin and Fentiazac. Moreover, there were significant increases in ovarian concentrations of PGF2 alpha and PGE2-PGE1 in response to Wy-40,972 that could be prevented by indomethacin. However, exogenous administration of either of these PG's was not effective in inducing ovulation in the hypx rat. Topics: Acetates; Adrenalectomy; Animals; Cyclooxygenase Inhibitors; Dinoprost; Estrus; Female; Gonadotropin-Releasing Hormone; Hypophysectomy; Indomethacin; Luteinizing Hormone; Median Eminence; Ovulation Induction; Pentobarbital; Pregnancy; Prostaglandins E; Prostaglandins F; Rats; Rats, Inbred Strains; Thiazoles | 1984 |