Spencer T E, Stagg A G, Ott T L, Johnson G A, Ramsey W S, Bazer F W
Department of Animal Science and Center for Animal Biotechnology and Genomics, Albert B. Alkek Institute of Biosciences and Technology, Texas A&M University System Health Science Center, College Station, Texas 77843-2471, USA.
Biol Reprod. 1999 Aug;61(2):464-70. doi: 10.1095/biolreprod61.2.464.
Interferon tau (IFNtau) is the antiluteolytic signal produced by the conceptus of ruminants. Intrauterine administration of recombinant ovine IFNtau suppresses expression of endometrial estrogen receptor (ER) and oxytocin receptor (OTR) in the luminal and superficial glandular epithelia to abrogate the production of luteolytic prostaglandin F(2alpha) (PGF(2alpha)) pulses. Subcutaneous (s.c.) injections of recombinant ovine (o) IFNtau appear to extend the interestrous interval by altering uterine PGF(2alpha) response to oxytocin. The present study tested the hypothesis that antiluteolytic effects of roIFNtau injected into the uterine lumen (paracrine) or s.c. (endocrine) are equivalent in suppressing expression of endometrial ER and OTR and inducing uterine expression of type I IFN-regulated Mx and ubiquitin cross-reactive proteins (UCRP). Sixteen cyclic ewes were fitted with uterine catheters on Day 5 (Day 0 = estrus), were assigned randomly to receive treatment with control proteins or roIFNtau (2 x 10(7) antiviral units/day) by either intrauterine or s.c. injections from Days 11 to 15, and were ovariohysterectomized on Day 16. Results indicated that expression of ER and OTR mRNAs in endometrial epithelium was suppressed by intrauterine but not by s.c. injections of roIFNtau. Intrauterine injections of roIFNtau increased expression of Mx and UCRP mRNA in the endometrium. Subcutaneous injections of roIFNtau increased endometrial Mx mRNA levels but not UCRP mRNA. Unexpectedly, intrauterine and s.c. injections of roIFNtau were equally effective in inducing expression of Mx and UCRP mRNA in the corpus luteum. Although s.c. injections of roIFNtau induced Mx mRNA in the endometrial epithelium, s.c. injections of roIFNtau did not abrogate activation of the uterine luteolytic mechanism by suppressing epithelial ER and OTR expression. Therefore, results of this study failed to support the assumption that endocrine roIFNtau mimics antiluteolytic effects of paracrine IFNtau to improve pregnancy rates in sheep.
干扰素τ（IFNτ）是反刍动物孕体产生的抗黄体溶解信号。子宫内给予重组羊IFNτ可抑制子宫内膜雌激素受体（ER）和催产素受体（OTR）在腔上皮和浅表腺上皮中的表达，从而消除黄体溶解前列腺素F（2α）（PGF（2α））脉冲的产生。皮下（s.c.）注射重组羊（o）IFNτ似乎通过改变子宫对催产素的PGF（2α）反应来延长发情间期。本研究检验了以下假设：注入子宫腔（旁分泌）或皮下（内分泌）的重组羊IFNτ在抑制子宫内膜ER和OTR表达以及诱导子宫表达I型干扰素调节的Mx和泛素交叉反应蛋白（UCRP）方面具有等效的抗黄体溶解作用。16只处于发情周期的母羊在第5天（第0天=发情期）安装子宫导管，从第11天到第15天随机分配接受对照蛋白或重组羊IFNτ（2×10⁷抗病毒单位/天）的子宫内或皮下注射，并在第16天进行卵巢子宫切除术。结果表明，子宫内注射重组羊IFNτ可抑制子宫内膜上皮中ER和OTR mRNA的表达，但皮下注射则无此作用。子宫内注射重组羊IFNτ可增加子宫内膜中Mx和UCRP mRNA的表达。皮下注射重组羊IFNτ可增加子宫内膜Mx mRNA水平，但不增加UCRP mRNA。出乎意料的是，子宫内和皮下注射重组羊IFNτ在诱导黄体中Mx和UCRP mRNA表达方面同样有效。虽然皮下注射重组羊IFNτ可诱导子宫内膜上皮中的Mx mRNA，但皮下注射重组羊IFNτ并不能通过抑制上皮ER和OTR表达来消除子宫黄体溶解机制的激活。因此，本研究结果未能支持内分泌重组羊IFNτ模拟旁分泌IFNτ的抗黄体溶解作用以提高绵羊妊娠率这一假设。
