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母猪空怀或配种不孕的原因有很多.调查表明,大约25%～35%的胚胎在妊娠12～18 d(胚胎着床期)发生流产,即隐性流产,给畜牧业带来巨大的损失.胚胎着床是一个复杂的,受很多因素调控的过程,着床窗口开放的时间也很短,此时胚胎发育到具有着床能力的阶段,子宫具有接受性.本文综述了关于猪胚胎着床时与黄体溶解相关的一些研究,主要包括瘦素及前列腺素在着床过程中的作用. 相似文献
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《畜牧兽医学报》2018,(11)
本研究旨在以肥大细胞和组织胺为指标探讨大鼠围着床期植物性神经与子宫局部细胞免疫的关系。选择180日龄,体重为300～350g的性成熟Wistar雌性大鼠90只,随机分为对照、假手术处理和手术处理(n=30)3组,手术处理为孕前切除支配子宫的植物性神经(肠系膜后神经节节后纤维和盆神经丛节前纤维),伤口愈合,开始合笼试验。在妊娠4～6d,无菌条件下,取出大鼠子宫和卵巢,观察排卵、胚胎着床情况变化,通过细胞染色和ELISA方法测定肥大细胞数量和组织胺释放量。结果表明:正常大鼠子宫中组织胺自发释放量和总含量在着床(d5)时最低。肥大细胞数量也呈现相似的变化。神经切除后,自发释放组织胺量在妊娠4～6d数值明显下降,且在妊娠4、6d与对照组相比较差异显著(P0.05);可释放组织胺总含量在着床前(d4)极显著降低(P0.01),且胚胎着床数量明显减少或延迟;肥大细胞数量在着床前后与组织胺总含量有相似的变化。这些结果说明,切除神经降低了着床前肥大细胞数量和组织胺水平,改变了子宫局部免疫水平,进而引起了胚胎着床减少或延迟。综上表明,支配子宫的植物性神经可在着床前上调子宫肥大细胞数量和组织胺水平,控制子宫局部免疫水平,在胚胎着床中起重要调控作用。 相似文献
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为了研究交感神经对小鼠胚胎着床和发育的作用机制,本文筛选出合适的L-苯丙氨酸浓度(320 mg/kg体重),处理孕鼠,观察胚胎着床和发育,通过甲苯胺蓝染色检测子宫局部肥大细胞的变化.研究结果显示,320 mg/kg体重L-苯丙氨酸能显著降低胚胎着床数目,分别下降了45％ (E7)和58％(E9),并且显著延缓胚胎的发育；与对照组相比,着床后子宫局部肥大细胞数目显著降低,分别在E5～E9降低了36.62％、64.59％和23.30％,差异显著.由本研究结果可以推断一定浓度的L-苯丙氨酸可以激活交感神经,影响妊娠早期子宫局部肥大细胞数量,从而改变子宫局部微环境,影响胚胎着床和发育. 相似文献
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选用成年雌性 Wistar大鼠 ,采用外科手术方法分别在妊娠前和妊娠后切断支配大鼠子宫的植物性神经 ,观察了切断神经对 Wistar大鼠着床的影响 ,并用常规组织学方法观察了子宫肥大细胞 ( MC)数的变化。结果表明 :( 1 )切断神经后再配种的大鼠不易怀孕 ,绝大部分鼠经交配 3次以上仍不怀孕 ,其他鼠推迟着床。对妊娠后大鼠切断神经并不影响妊娠的维持 ;( 2 )切断神经的大鼠子宫 MC总数与对照组相比有所增加 ,经 t检验未见显著差异 ,提示神经影响着床不完全是通过 MC数的改变起作用 ,可能通过改变 MC介质的释放起作用。本试验结果提示 ,支配子宫的植物性神经可能参与大鼠胚胎着床的建立 ,而对胚胎着床后影响并不重要 相似文献
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Lei FAN Menghan SHA Wei LI Qingling KANG Jianli WU Suhua CHEN Nan YU 《The Journal of reproduction and development》2021,67(6):359
Immune imbalance of Treg/Th17 cells may contribute to recurrent implantation failure (RIF) during in vitro fertilization and embryo transfer (IVF-ET). In this study, we sought to determine the effect of intrauterine administration of mouse PBMCs prior to embryo implantation on endometrial receptivity and embryo implantation, and examine the underlying mechanism of Treg/Th17 cell balance following intrauterine administration of PBMCs. Pregnant mice were randomly divided into three groups: control group, embryo implantation dysfunction (EID) group, and EID with PBMCs group, and the number of embryo implantation sites was recorded during early pregnancy (Pd7.5). The balance of Treg/Th17 cells in the peripheral blood, spleen, and local implantation sites was detected during the peri-implantation period (Pd4.0) and early pregnancy (Pd7.5). The EID group demonstrated a significant decrease in the number of embryo implantation sites, while the EID with PBMCs group demonstrated higher number of embryo implantation sites compared to the EID group. The balance of Treg/Th17 cells in the peripheral blood and spleen tissues was not significantly different between the aforementioned groups. However, the local uterine ratio of the Treg/Th17 cells increased in the EID with PBMCs group compared to that in the EID group. Collectively, we found that intrauterine administration of PBMCs prior to embryo implantation effectively promotes embryo implantation rates. This may be attributed to the improvement in the local immune balance of Treg and Th17 cells compared with the overall immune balance. 相似文献
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附植是指哺乳动物囊胚滋养层细胞与母体子宫上皮细胞之间逐步建立组织生理上联系的过程。成功的附植有赖于胚泡与母体相互识别,胚泡发育与母体子宫变化的同步以及抑制母体的免疫排斥反应和母体接受性等一系列事件。这些事件又受到母体和胚泡的激素以及一些因子的调控。传统中药可通过提高孕酮的含量、类雌激素样作用、治疗子宫内膜炎的作用以及影响白血病抑制因子和白细胞介素1的表达量来促进山羊胚胎附植。文章主要论述了哺乳动物胚胎附植的机制以及中药对胚胎附植的影响,这有助于进一步阐明中药保胎的作用机理。 相似文献
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Abstract: Relationship between the implantation of the tails and the fertility in boars In this study ejaculates of 47 different breed and age boars were examined. The aim of this study was to determine the relationship between the implantation of the tails and the fertility in boars. From the evaluation of 115 ejaculates it was observed that the rate of abaxial implantation of the tails in ejaculates of boars was very fluctuating. The rate of axial and abaxial implantation of the tails was stable in the ejaculates of the same boars. Although some studies indicate that abaxial implantation can be the reason for infertility the present authors observed better fertilisation results with ejaculates having higher percentages of abaxial spermatozoa. 相似文献
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Wollenhaupt K Reinke K Brüssow KP Spitschak M Kanitz W Tomek W 《Reproduction in domestic animals》2011,46(5):917-919
The mechanism of implantation is species specific (pig: epitheliochorial, bovine: synepitheliochorial, mouse: hemochorial). Recently, we have shown that proteolytical cleavage of the prototypical 25 kDa mRNA cap-binding protein eIF4E (eukaryotic initiation factor 4E) produces a stable variant with a molecular mass of approximately 23 kDa in porcine endometrium at the time of implantation. Here, we investigate if an eIF4E truncation also takes place in the endometrium of species with other implantation forms. Thus, eIF4E and its repressor protein 4E-BP1 were investigated in porcine, murine and bovine endometrium during the time of implantation. Our results show that eIF4E truncation is specific for the porcine implantation. In bovine and mouse uterine tissue, no cleavage of eIF4E was observed. Whereas no difference of bovine 4E-BP1 was found, in murine samples, increased phosphorylation during implantation was observed. However, porcine samples exhibit an opposite behaviour, the abundance and mainly the phosphorylation of 4E-BP1 decrease. We propose that the translation initiation in the endometrium is differently regulated by the two eIF4E forms with regard to different 4E-BP1 abundance and phosphorylation as well as different eIF4E/4E-BP1 binding dynamic depending on the type of implantation. 相似文献
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产仔数性状是养猪业中一个重要的经济性状,而胚胎附植对猪产仔数的高低有重要的影响。胚胎附植的调控涉及到多个生物学过程,在其中发挥作用的物质（附植因子）很多。作者针对孕酮、孕酮受体、雌二醇、雌激素受体α（ESR1）和促红细胞生成素产生肝细胞受体配体（Eph-ephrin）系统这几种附植因子的相关研究进行了归纳总结,重点阐述了这些因子在母胎对话过程中的时空表达、功能、突变、调控等方面的研究进展。其中,孕酮及其受体在猪胚胎附植活动中全程发挥着重要作用,黄体分泌的孕酮与母猪子宫内膜腔上皮、腺上皮、基质和肌细胞中的孕酮受体结合发挥作用,使这些组织细胞分泌多种附植因子,这些附植因子进一步参与胚胎附植过程。雌二醇是雌激素中含量最多、活性最强的一种激素,主要由卵巢颗粒细胞分泌,雌激素受体α是子宫内雌二醇的主要受体,二者结合可使母猪发情;此外,附植中处于游离状态的胚泡也分泌雌二醇,其是一个让母猪子宫内膜得以识别的信号,允许胚泡附植。Eph-ephrin系统作用广泛,其在人、小鼠和猪的胚胎附植过程中发挥着重要作用。系统中的EphA1、ephrin A1、EphA4等基因在猪的胚胎附植期表达量显著高于空怀猪,它们在子宫内膜附植点的表达量显著高于附植点间的部位,且ephrin A1的抑制表达会降低子宫内膜上皮细胞的迁移和黏附能力。这些附植因子都在猪胚胎附植活动中发挥着重要作用,对它们的深入研究将有利于明确猪胚胎附植调控机理,进一步揭示猪高繁机理。 相似文献
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Tissue and fluid changes occurring within tissue chambers were characterised as a function of time after subcutaneous implantation in cattle. Cytological and chemical investigation revealed that the composition of fluid within chambers approached the theoretical composition of true interstitial fluid as time after implantation progressed. Erythrocyte and leucocyte numbers decreased sharply immediately after implantation and had reached stable numbers by 40 days after implantation. At this stage, chamber fluid samples had lower total protein and albumin concentrations, higher K+ and Cl- concentrations and lower pH than corresponding blood samples. Despite an ongoing low-grade chronic inflammatory reaction resulting in fibrous encapsulation of chambers, the vascularity of chamber tissue did not diminish with time after implantation. By 40 days after implantation, the cellular and chemical constituents had stabilised enough to allow use of the model to study drug distribution. 相似文献