title: Aglepristone (RU534) effects on luteal function of pseudopregnant rabbits: steroid receptors, enzymatic activities, and hormone productions in corpus luteum and uterus.
abstract: The study was designed to examine the aglepristone (RU534) mechanisms affecting the corpora lutea (CL) lifespan in pseudopregnant rabbits. Aglepristone (10 mg/kg b.w.) was injected subcutaneously twice at either early- or mid-luteal phase (Days 3 and 4, or Days 8 and 9, respectively) after induction of ovulation with GnRH (Day 0). Corpora lutea and uteri, explanted at days 6 and 11, were evaluated for immunohistochemistry and Western blotting of progesterone (PR) and estrogen (ER) receptors, cyclooxygenase 1 (COX1), COX2, and PGE2-9-ketoreductase (PGE2-9-K) enzymatic activities, and progesterone, PGF2α, and PGE2 in vitro synthesis. Independent of luteal stage, aglepristone prolonged the functional luteal phase by 3 Days over that of controls as assessed by blood progesterone profiles. Aglepristone decreased protein for ER during both luteal-stages in CL and uteri. Progesterone receptor protein was decreased by RU354 at Days 6 in the uterus and at Days 11 in CL, whereas RU534 increased PR at Days 11 in uteri. In the CL, RU534 enhanced progesterone production at Days 6 and 11, whereas it decreased PGF2α and increased PGE2 at Day 11. In the uteri, RU534 decreased PGF2α and increased PGE2 synthesis at both days. COX2 and PGE2-9K activities were decreased by RU534 in the CL at Day 11, whereas in the uteri COX2 increased and PGE2-9-K decreased at Days 6 and 11. In conclusion, these data on aglepristone effects suggest that progesterone has a regulatory role on luteal function through direct and uterine-mediated mechanisms in pseudopregnant rabbits.
authors.affiliation: Scuola di Scienze mediche veterinarie, Università di Camerino, Matelica, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Parillo
authors.affiliation: Dipartimento di Scienze biopatologiche veterinarie ed Igiene delle produzioni animali e alimentari, Università di Perugia, Perugia, Italy.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Dall'Aglio
authors.affiliation: Dipartimento di Scienze biopatologiche veterinarie ed Igiene delle produzioni animali e alimentari, Università di Perugia, Perugia, Italy.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Brecchia
authors.affiliation: Dipartimento di Scienze biopatologiche veterinarie ed Igiene delle produzioni animali e alimentari, Università di Perugia, Perugia, Italy.
authors.forename: Margherita
authors.initials: M
authors.lastname: Maranesi
authors.affiliation: Dipartimento di Patologia, Clinica e Diagnostica veterinaria, Università di Perugia, Perugia, Italy.
authors.forename: Angela
authors.initials: A
authors.lastname: Polisca
authors.affiliation: Dipartimento di Scienze biopatologiche veterinarie ed Igiene delle produzioni animali e alimentari, Università di Perugia, Perugia, Italy.
authors.forename: Cristiano
authors.initials: C
authors.lastname: Boiti
authors.affiliation: Scuola di Scienze mediche veterinarie, Università di Camerino, Matelica, Italy. Electronic address: massimo.zerani@unicam.it.
authors.forename: Massimo
authors.initials: M
authors.lastname: Zerani
mesh_terms: D000818:Animals; D015153:Blotting, Western / Q000662:veterinary; D003338:Corpus Luteum / Q000201:enzymology / Q000378:metabolism*; D051545:Cyclooxygenase 1 / Q000032:analysis; D051546:Cyclooxygenase 2 / Q000032:analysis; D015237:Dinoprost / Q000032:analysis; D015232:Dinoprostone / Q000032:analysis; D004963:Estrenes / Q000494:pharmacology*; D005260:Female; D006911:Hydroxyprostaglandin Dehydrogenases / Q000032:analysis; D007150:Immunohistochemistry / Q000662:veterinary; D008183:Luteal Phase / Q000502:physiology; D011374:Progesterone / Q000097:blood; D011555:Pseudopregnancy / Q000378:metabolism*; D011817:Rabbits / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000032:analysis; D011980:Receptors, Progesterone / Q000032:analysis; D018709:Statistics, Nonparametric; D014599:Uterus / Q000201:enzymology / Q000378:metabolism*
chemical_list: D004963:Estrenes; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C419063:aglepristone; D011374:Progesterone; D015237:Dinoprost; D006911:Hydroxyprostaglandin Dehydrogenases; C035858:prostaglandin-E2 9-reductase; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D015232:Dinoprostone