REGULATION OF PROTEIN AND PROSTAGLANDIN SECRETION IN POLARIZED PRIMARY CULTURES OF CAPRINE UTERINE EPITHELIAL-CELLS

Caprine uterine epithelial (UE) cells were cultured on Matrigel-coated filters. Transmission electron microscopy revealed polarized UE cells characterized by basally located nuclei, apical microvilli, convolute d lateral membranes, and junctional complexes. Domain-specific secreti on of prostaglandins and radiolabeled proteins provide further evidenc e of functional epithelial cell polarity. Two experiments were conduct ed to evaluate factors controlling prostaglandin E-2 (PGE) and prostag landin F-2 alpha (PGF) secretion. In experiment one, steroid-treated ( estradiol, progesterone, or estradiol + progesterone) polarized UE cel ls were treated with interferon tau (IFN tau) and/or oxytocin (OT). St eroid treatment did not influence PGE or PGF secretion. However, analy sis of variance revealed an IFN tau by OT interaction (P <.01) for bot h PGE and PGE This interaction was caused by a reduction in PGE and PG F secretion by cultures receiving only IFN tau and the inability of IF N tau to block OT-induced release of PGE or PGF. In experiment 2, pola rized UE cells were cultured in progesterone, with or without IFN tau, and sequentially challenged with estradiol and OT. Oxytocin stimulate d the release of both PGE and PGF by polarized cUE cells (P <.01) and resulted in an increased accumulation of PGE (OTdomain; P <.01) in th e basal compartment. Interferon tau did not influence PGE (P <.1) secr etion. However, further analysis revealed that IFN tau reduced PGF sec retion and was unable to block OT-induced PGF secretion (IFN tauOT; P <.05) by polarized UE cells. Therefore, caprine UE cells form polariz ed monolayers and retain responsiveness to IFN tau and OT in vitro.