Grzesiak M, Knapczyk-Stwora K, Slomczynska M
Department of Endocrinology, Institute of Zoology, Jagiellonian University in Krakow, Gronostajowa 9, 30-383 Krakow, Poland; Department of Animal Physiology and Endocrinology, University of Agriculture in Krakow, Al. Mickiewicza 24/28, 30-059 Krakow, Poland.
Department of Endocrinology, Institute of Zoology, Jagiellonian University in Krakow, Gronostajowa 9, 30-383 Krakow, Poland.
Domest Anim Endocrinol. 2017 Apr;59:81-89. doi: 10.1016/j.domaniend.2016.12.001. Epub 2016 Dec 11.
Recently, we have indicated that flutamide-induced androgen deficiency diminished progesterone production in the porcine corpus luteum (CL) during late pregnancy and before parturition, as a sign of functional luteolysis. In pigs, the main luteolytic factor is prostaglandin F (PGF), which acts via specific receptors (PTGFRs), and its biosynthesis is catalyzed by prostaglandin F synthase (PGFS). The present study investigated the impact of flutamide on luteal PGFS and PTGFR expression, as well as intraluteal PGF content during pregnancy in pigs. Flutamide (50 mg/kg BW per day, for 7 d) or corn oil (control groups) were administered subcutaneously into pregnant gilts (n = 3 per group) between 83 and 89 (GD90) or 101-107 (GD108) days of gestation (GD). On GD90 and GD108 ovaries were collected and CLs were obtained. Real-time PCR and Western blot analyses were conducted to quantify PGFS and PTGFR mRNA and protein expression, respectively. In addition, immunohistochemical localization of both proteins was performed and the concentration of PGF was analyzed by enzyme immunoassay method. Flutamide caused upregulation of PGFS mRNA and protein in GD90F (P = 0.008; P = 0.008, respectively) and GD108F (P = 0.041; P = 0.009, respectively) groups. The level of PTGFR mRNA increased only in the GD90F (P = 0.007) group, whereas PTGFR protein expression was greater in both gestational periods (P = 0.035; P = 0.038, respectively). On GD90 PGFS was immunolocalized in the cytoplasm of large luteal cells only, whereas on GD108, sparse small luteal cells also displayed positive staining. PTGFR showed membranous localization within large luteal cells on both days of pregnancy. In luteal tissue, PGF concentration was greater after flutamide exposure on both days (P = 0.041; P = 0.038, respectively), when compared with control groups. Overall, the enhanced luteal PGF content due to increased PGFS expression after flutamide administration might contribute to premature CL regression. Moreover, higher PTGFR protein levels indicate enhanced sensitivity of luteal cells to PGF under androgen deficiency.
最近，我们指出，氟他胺诱导的雄激素缺乏会在妊娠后期和分娩前减少猪黄体（CL）中的孕酮生成，这是功能性黄体溶解的一个标志。在猪中，主要的黄体溶解因子是前列腺素F（PGF），它通过特定受体（PTGFRs）发挥作用，其生物合成由前列腺素F合酶（PGFS）催化。本研究调查了氟他胺对猪妊娠期黄体PGFS和PTGFR表达以及黄体中PGF含量的影响。在妊娠第83至89天（妊娠90天，GD90）或第101至107天（妊娠108天，GD108），将氟他胺（50mg/kg体重/天，持续7天）或玉米油（对照组）皮下注射到妊娠母猪（每组n = 3）体内。在GD90和GD108收集卵巢并获取黄体。分别进行实时PCR和蛋白质印迹分析以量化PGFS和PTGFR mRNA及蛋白质表达。此外，对这两种蛋白质进行免疫组织化学定位，并通过酶免疫测定法分析PGF浓度。氟他胺导致GD90F组（分别为P = 0.008；P = 0.008）和GD108F组（分别为P = 0.041；P = 0.009）中PGFS mRNA和蛋白质上调。PTGFR mRNA水平仅在GD90F组中升高（P = 0.007），而PTGFR蛋白质表达在两个妊娠期均更高（分别为P = 0.035；P = 0.038）。在GD90，PGFS仅在大黄体细胞的细胞质中免疫定位，而在GD108，稀疏的小黄体细胞也显示阳性染色。在妊娠的这两天，PTGFR在大黄体细胞内均显示膜定位。与对照组相比，在这两天氟他胺暴露后黄体组织中的PGF浓度更高（分别为P = 0.041；P = 0.038）。总体而言，氟他胺给药后由于PGFS表达增加导致黄体PGF含量增加可能有助于黄体过早退化。此外，较高的PTGFR蛋白质水平表明在雄激素缺乏情况下黄体细胞对PGF的敏感性增强。
