RESUMO
Endometrial oxytocin receptors and total production of PGF by endometrial epithelial cells were measured in 10 cyclic cows after intrauterine injections of recombinant bovine interferon-tau plus BSA or BSA alone. Cows received twice daily injections (via intrauterine catheters) of 200 micrograms of recombinant bovine interferon-tau plus 1.3 mg of BSA (n = 5) or 1.5 mg of BSA (n = 5) from d 14 to 17 after estrus. On d 17, the reproductive tracts of each cow was removed at slaughter, and endometrial epithelial cells were cultured with 0, 2, or 50 ng/ml of recombinant bovine interferon-tau. After 24 h, oxytocin (2 x 10(-7) M) was added to one-half of the culture wells, and the medium was sampled at 0, 30, and 90 min for analysis of total PGF (PGF plus 13, 14-dihydro-15-keto-PGF2 alpha). In vivo treatment with recombinant bovine interferon-tau + BSA reduced total secretion of PGF in culture (1.49 +/- 0.06 vs. 2.80 +/- 0.07 ng/micrograms of DNA), but did not block the oxytocin-induced stimulation in total secretion of PGF. In vitro treatment of cells with recombinant-bovine interferon-tau did not decrease basal secretion of total PGF. Oxytocin receptor binding at d 17 was low in both treatments but slightly attenuated in the group treated with recombinant bovine interferon-tau.
