title: The effect of estrone and estradiol treatment on endometrial total protein, uteroferrin, and retinol-binding protein secretion during midpregnancy or midpseudopregnancy in swine.
abstract: It has been hypothesized that conceptus estrogens influence endometrial protein secretion during pregnancy in swine. To test this hypothesis, the effect of estrone and estradiol treatment from d 30 to 60 of pregnancy or pseudopregnancy on endometrial protein secretion was investigated. Pregnant (P; n = 16) and pseudopregnant (PP) gilts (n = 18) received either sham treatment or estrone or estradiol implants (5 mg/d release rate; 60 d release) on d 30 of P or PP. Blood samples were collected on d 30, 40, 50, and 60 to measure estrone and estradiol. On d 60, gilts were hysterectomized. For P gilts, endometrium in apposition to one placenta from each uterine horn was collected. For PP gilts, each uterine horn was flushed with 40 mL of leucine-deficient minimal essential medium (MEM), and endometrial tissue was collected from each horn. Endometrial tissues were incubated in MEM in the presence of 50 microCi of [3H]leucine to examine protein secretion. Estrone and estradiol treatments increased both plasma and endometrial concentrations of estrone (P < .01 except endometrium for P gilts) and estradiol (P < .01, respectively). Endometrium from P gilts secreted more nondialyzable macromolecules (NDM), acid phosphatase activity (AP, a measure of uteroferrin), and retinol-binding protein (RBP) in culture than did endometrium from PP gilts. Estrone treatment increased (P < .01) endometrial NDM from P gilts but not that from PP gilts; estradiol had no effect. Both estrone and estradiol increased (P = .069) endometrial secretion of AP of PP but not of P gilts. Endometrial secretion of RBP was not affected by either estrone or estradiol treatment. Neither estrone nor estradiol affected total protein or AP and estrone treatment decreased (P < .05) RBP in uterine flushings from PP gilts. These data indicate that endometrium from P pigs secretes more protein than endometrium from PP pigs but neither estrone nor estradiol completely mimics the effect of pregnancy.
authors.affiliation: USDA, ARS, Roman L. Hruska U.S. Meat Animal Research Center, Clay Center, NE 68933, USA.
authors.forename: J L
authors.initials: JL
authors.lastname: Vallet
authors.forename: R K
authors.initials: RK
authors.lastname: Christenson
mesh_terms: D000135:Acid Phosphatase / Q000032:analysis / Q000378:metabolism; D000818:Animals; D004717:Endometrium / Q000737:chemistry / Q000201:enzymology / Q000378:metabolism*; D004958:Estradiol / Q000032:analysis / Q000097:blood / Q000494:pharmacology*; D004970:Estrone / Q000032:analysis / Q000097:blood / Q000494:pharmacology*; D005260:Female; D007527:Isoenzymes; D008667:Metalloproteins / Q000378:metabolism*; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism*; D011555:Pseudopregnancy / Q000378:metabolism / Q000662:veterinary*; D012177:Retinol-Binding Proteins / Q000378:metabolism*; D054839:Retinol-Binding Proteins, Plasma; D013552:Swine / Q000378:metabolism*; D013553:Swine Diseases / Q000378:metabolism*; D000071681:Tartrate-Resistant Acid Phosphatase
chemical_list: D007527:Isoenzymes; D008667:Metalloproteins; D011506:Proteins; D012177:Retinol-Binding Proteins; D054839:Retinol-Binding Proteins, Plasma; D004970:Estrone; D004958:Estradiol; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase