15-keto-13-14-dihydroprostaglandin-f2alpha and Anovulation

The objective was to determine differences in follicle and reproductive hormone characteristics in mares with ovulatory and flunixin meglumine (FM)-induced anovulatory cycles. Estrous mares were given 1500 IU hCG when the follicle was ≥ 32 mm (0 h). In Experiment 1, control mares (n = 7) were not treated further. The remaining mares (n = 11) were given 1.7 mg/kg FM i.v. twice daily, from 0 to 36 h after hCG treatment. Blood samples and ultrasonographic examinations were performed every 12 h. All control mares ovulated normally between 36 and 48 h. In contrast, eight of 11 FM mares did not ovulate, but developed luteinized unruptured follicles (LUFs). Three FM-treated mares did not develop conventional LUFs. Plasma progesterone concentrations were lower (P < 0.05) in LUF mares at 96, 120, and 216 h than in controls, whereas plasma LH concentrations were higher (P < 0.05) between 108 and 120 h in LUF mares than in controls. Plasma concentrations of PGFM and estradiol did not differ significantly between groups. In Experiment 2, the three mares that did not develop LUFs were treated, during the consecutive cycle, with the same dose of FM but with increased frequency at zero, 12, 24, 30, 36, and 48 h after hCG. One mare formed a LUF, whereas the other two did not. These two mares had lower LH concentrations than LUF or control mares in the two consecutive cycles. In conclusion, systemic treatment with FM blocked ovulation in 73% of treated mares. Mares with LUFs had lower progesterone and higher LH concentrations than control mares.

Topics: Animals; Anovulation; Chorionic Gonadotropin; Clonixin; Dinoprost; Estradiol; Female; Hormones; Horses; Luteinization; Luteinizing Hormone; Ovarian Follicle; Ovulation; Progesterone; Prostaglandin Antagonists; Ultrasonography

Highly specific antibodies to 13, 14-dihydro-15-ketoprostaglandin F2 alpha (PGFM) were raised in rabbits. The animals were immunized with PGFM-bovine serum albumin (BSA)-conjugates. Prior to the incubation procedure PGFM was extracted by a rapid method with dichloromethane followed by column chromatography. The antisera dilution was 1:10 000 amd the cross-reactivity towards prostaglandin A2, E2, F2 alpha, 13, 14-dihydro-15-ketoprostaglandin E2 and the 15-ketoprostaglandin E2 and F2 alpha 2 was less than 1%. The limit of detection was 1.9 +/- 0.6 pg/ml plasma over the standard range 1.9--250 pg. The intra- and inter-assay variations were 3.9 and 15%, respectively. PGFM was measured throughout the menstrual cycle in female volunteers. In normal ovulatory women (n = 3) plasma levels of PGFM varied between 65.6 to 107.1 pg/ml. No significant variations of plasma PGFM were seen during the cycle. In anovulatory women (n = 4) no difference of PGFM was found during the cycle. PGFM levels in hyperprolactinaemic but ovulating women tend to be higher than in anovulatory, and normoprolactinaemic subjects. These data strongly indicate that PGFM is not correlated with other hormonal parameters tested here in the normal and anovulatory cycles.

Topics: Adult; Anovulation; Dinoprost; Estradiol; Female; Follicle Stimulating Hormone; Humans; Luteinizing Hormone; Menstruation; Ovulation; Progesterone; Prolactin; Prostaglandins F; Radioimmunoassay