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家畜黄体的退化取决于子宫释放的PGF2α。尽管PGF2α在溶黄体中起主要作用,但人们对PG诱导黄体细胞水平退化的实际机制还知之甚少。迄今许多研究都把焦点集中到PGF2α活动的细胞位置上,而且这种化合物看来似乎对黄体细胞能产生多种效应。大黄体细胞可能最初对溶黄体信号起反应,但退化过程也许需要大小黄体细胞以及黄体细胞和非黄体细胞之间的交流传达。免疫系统似乎有效地包含在溶黄体过程中,因此黄体细胞向某种类型的免疫细胞传递有效的信号是可能的。目前已知黄体细胞可与多种免疫细胞分泌物起反应,这种见解可能会导致涉及黄体退化的其它机制的发现。 相似文献
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反刍家畜黄体的退化取决于子宫释放的ＰＧＦ２α，然而ＰＧ诱导黄体细胞水平退化的实际机制尚知之甚少，许多研究认为ＰＧＦ２α对黄体细胞似乎能产生多种效应。大黄体细胞可能最初对溶黄体信号起反应，但其退化过程也许需要大小黄体细胞间以及黄体细胞与非黄体细胞间的交流传达。免疫系统似乎被有效地包含在溶黄体过程中，因胞分泌物起反应，这也许会导致涉及黄体退化的其它机制的发现。 相似文献
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哺乳动物发情周期黄体的组织学研究进展 总被引：1，自引：0，他引：1
黄体是排卵后形成的暂时性的内分泌组织 ,在一个较短的存在期限中经历了一系列的结构变化和分泌阶段 ,对于哺乳动物维持正常的生殖功能具有重要作用。人们对黄体细胞的来源、组成、形态及大小持有不同的观点。近年来 ,人们就黄体细胞的功能和退化、溶解进行了较为深入的研究 ,发现不同动物黄体细胞的功能各有不同 ,黄体退化、溶解与细胞凋亡有密切关系。了解哺乳动物发情周期黄体的组织结构对于控制动物的繁殖具有重要意义。文章对哺乳动物发情周期黄体中不同类型黄体细胞的来源、组成、形态、功能及退化、溶解 ,黄体细胞的分泌方式和超声波在黄体研究中的运用作了概述 相似文献
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犬黄体具有异于其他家畜的生理结构和功能表现,其中最特别的是犬缺乏急性黄体溶解机制。犬黄体发生过程受催乳素、促黄体素和前列腺素E2的复杂调控,溶解退化过程则对其他家畜主要的溶黄体激素--前列腺素F2α不敏感。而黄体的存留对母犬的生殖活动却具有重要的意义,其自分泌或旁分泌的类固醇激素也在妊娠调控和发情周期的更迭中发挥重要作用。犬黄体的退化机制尚未明确,但国外已有包括被动退化在内的诸多假说。此外,黄体是为数不多具有完整生命周期的功能性组织（或器官）,其发生过程、功能实现和衰老溶解都在周而复始地进行,这对炎症反应、癌症发生和细胞凋亡等研究都具有重要的参考价值。作者综述了犬黄体的发生和退化过程中调控机制的研究进展,旨在为进一步深入研究犬黄体发生和退化的分子机制提供研究背景和理论依据。 相似文献
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卵泡囊肿分为三型:卵泡囊肿、黄体囊肿和囊肿性黄体。第一、二型囊肿引起暂时性不育,而囊肿性黄体却不是病理性的。治疗卵巢囊肿,应该提高两种激素疗法:(1)对卵泡囊肿病例,使用促黄体制剂,如人绒毛膜促性激素(HCG)和促性腺素释放激素(GnRH)(以引起黄体化);(2)对黄体囊肿应用溶黄体物质,如前列腺素(PGF2_α) (引起黄体组织退化,出现正常性周期)。因而,从实用的观点看,鉴别诊断卵巢 相似文献
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干扰素-τ及其在反刍动物中抗黄体溶解作用 总被引：1，自引：1，他引：0
干扰素-τ是一个在反刍动物妊娠建立过程中起着关键性作用的细胞因子,属于Ⅰ型干扰素家族。在围植入期由胚胎滋养层单核细胞合成分泌,主要作用于子宫内膜,抑制溶黄体素PGF2α的合成分泌,起到抗黄体溶解作用,保证妊娠的建立。导致牛胚胎早期死亡的一个重要原因是抗黄体溶解机制失调,因此干扰素-τ被认为是一个能有效提高妊娠率的可操控靶细胞因子。 相似文献
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旨在研究不同黄体期注射前列腺激素(PGF2α)对湖羊育成母羊黄体组织形态、PGF2α受体及程序性坏死通路基因表达的影响。本研究选择健康、体况良好、体重相近经同期发情处理的母羊48只，随机均分为6组，分别为黄体前期试验组和对照组、中期试验组和对照组和末期试验组和对照组母羊，试验组在发情周期第6天(黄体前期)、11天(黄体中期)、16天(黄体末期)注射1 mL PGF2α(0.1 mg),对照组在相同时间注射1 mL生理盐水，每次注射后3 h采集黄体组织，用于基因表达检测及HE组织染色检测黄体组织形态变化。结果表明，注射PGF2α后试验羊黄体组织形态发生了变化，出现炎症细胞浸润与细胞凋亡，其中黄体中期退化程度最高。未注射PGF2α的母羊，黄体前期、中期FPA mRNA表达水平显著高于黄体末期(P<0.05);黄体前期FPB表达水平显著高于黄体末期(P<0.05),与黄体中期无显著差异(P>0.05);黄体中期TNFR1表达水平显著高于黄体前期和末期(P<0.05);黄体中期RIPK3表达水平显著高于黄体末期(P<0.05),黄体中、末期与黄体前期差异均不显著(... 相似文献
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《畜牧与兽医》2017,(4):1-5
通过分析NR4A1在猪卵巢黄体中的表达与定位,探讨其在猪黄体发育与退化中的潜在作用。获取猪发情周期不同阶段卵巢组织,分离黄体(早期、中期和晚期),应用放射免疫法检测孕酮和雌二醇浓度,应用蛋白免疫印迹法检测NR4A1、CYP17A1和cleaved-Caspase-3的表达,应用免疫组织化学方法检测NR4A1和cleaved-Caspase-3的定位。结果:晚期黄体(白体)的孕酮水平显著低于早期和中期,雌二醇水平显著高于早期和中期(P0.05);早期黄体(红体)与中期黄体的NR4A1表达量无显著差异,而晚期黄体(白体)中NR4A1显著低于早期和中期(P0.05);CYP17A1在早期黄体与中期黄体无显著差异,晚期黄体显著上升;cleaved-Caspase-3在中期黄体中表达最低,而在晚期黄体中最高(P0.05)。此外,整个黄体发育与退化过程中,NR4A1主要在黄体类固醇生成细胞的细胞质中表达,而cleaved-Caspase-3在包括黄体类固醇生成细胞的所有细胞中均有表达。结果提示:猪卵巢黄体发育与退化过程中,NR4A1的蛋白表达趋势与孕酮水平一致,NR4A1可能参与调控猪黄体组织中孕酮的合成代谢,为深入研究NR4A1参与猪卵巢机能调控提供理论依据。 相似文献
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Shirasuna K Akabane Y Beindorff N Nagai K Sasaki M Shimizu T Bollwein H Meidan R Miyamoto A 《Domestic animal endocrinology》2012,43(3):227-238
Prostaglandin F(2α) (PGF(2α)) induces luteolysis via a specific receptor, PTGFR. Although PTGFR mRNA expression in the bovine corpus luteum (CL) has been studied previously, changes in PTGFR protein and its localization are not fully understood during the life span of the CL. In addition to full-length PTGFR, several types of PTGFR isoforms, such as PTGFRα (type I) and PTGFRζ (type II), were reported in the bovine CL, suggesting isoform-specific luteal action. Full-length PTGFR mRNA in the bovine CL increased from the early to the mid-luteal phase and decreased during luteolysis, whereas PTGFR protein remained stable. PTGFR protein was localized to both luteal and endothelial cells and was expressed similarly during the life span of the CL. Like full-length PTGFR mRNA, PTGFRα and PTGFRζ mRNA also increased from the early to mid-luteal phases, and mRNA of PTGFRζ, but not PTGFRα, decreased in the regressing CL. During PGF(2α)-induced luteolysis, the mRNAs of full-length PTGFR, PTGFR,α and PTGFRζ decreased rapidly (from 5 or 15 min after PGF(2α) injection), but PTGFR protein decreased only 12 h later. Silencing full-length PTGFR using small interfering RNA prevented PGF(2α)-stimulated cyclooxygenase-2 (PTGS2) mRNA induction. By contrast, PGF(2α) could stimulate vascular endothelial growth factor A (VEGFA) mRNA even when full-length PTGFR was knocked down, thus suggesting that PGF(2α) may stimulate PTGS2 via full-length PTGFR, whereas VEGFA is stimulated via other PTGFR isoforms. Collectively, PTGFR protein was expressed continually in the bovine CL during the estrous cycle, implying that PGF(2α) could function throughout this period. Additionally, the bovine CL expresses different PTGFR isoforms, and thus PGF(2α) may have different effects when acting via full-length PTGFR or via PTGFR isoforms. 相似文献
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The effect of a single injection of prostaglandin F2alpha (PGF) during mid-diestrus on systemic concentrations of progesterone, LH, FSH, estradiol, and cortisol and on blood flow to the corpus luteum was studied in 10 controls and 10 PGF-treated mares. Blood flow was assessed by estimating the percentage of corpus luteum with color-Doppler signals of blood flow during real-time scanning of the entire structure and by the diameter of the vascular pedicle near its attachment to the ovary. Treatment was done 8 days after ovulation and 0 h was immediately before the treatment. Examinations and collection of blood samples were done at 0 h, every 5 min until 1h, and then at 1.5, 2, 4, 8, 12, 24, 48, and 72 h. The concentrations of estradiol did not change, but progesterone, LH, FSH, and cortisol increased significantly within 5 min. Concentrations of LH and FSH in the PGF group remained elevated until a temporarily lower concentration at 8 or 4h, respectively, rebounded to 12h, and then slowly decreased. Cortisol remained elevated, until a decrease between 1 and 4h. Progesterone in the PGF group increased significantly until 10 min after 0 h and then decreased by 40 min to below the concentrations in controls. Within the PGF group, progesterone decreased significantly by 45 min to below the concentrations at 0 h. The values for each of the two indicators of blood flow did not differ significantly between the PGF and control groups until a decrease at 24h in the PGF group. Results did not support the hypothesis that the immediate transient post-PGF increase in progesterone was associated with an increase in luteal blood flow. Luteolysis, as indicated by decreasing progesterone, began well before the beginning of a decrease in luteal blood flow. 相似文献
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黄体释放的黄体酮对母畜发情周期、启动发情行为和维持妊娠起着至关重要的作用,但目前国内外对黄体是否影响胚胎移植效果有着不同报道。本文以探究黄体对牛胚胎移植效果的影响为主线,查阅大量文献,归纳黄体的检查和级别判断方法,分别分析黄体大小、黄体位置、黄体质量和黄体生产溶解过程激素水平与胚胎移植受胎率的关系,为提高胚胎移植效果提供科学的参考依据。生产上常通过B超扫描结合直肠检查法判断受体牛黄体发育和位置作为能否移植的依据;由各学者研究结果可见,不同直径黄体的胚胎移植受胎率差异不显著,为提高受体牛的利用,在对受体牛黄体大小选择时可适当放宽标准;胚胎移植到黄体同侧的受胎率比移植到黄体对侧的高,另外,可能因为操作者左右手操作习惯不同,发现左侧黄体移植受胎率比右侧的要高;较多学者认为质量好的胚胎选择黄体质量好的受体移植才能得到更高的受胎率;胚胎移植后能否成功受孕,还与黄体生成溶解过程中孕酮含量及孕酮与雌二醇的比例等有关。 相似文献
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Ferreira-Dias G Bravo PP Mateus L Redmer DA Medeiros JA 《Domestic animal endocrinology》2006,30(4):247-259
Corpus luteum growth and endocrine function are closely dependent on the formation of new capillaries. The objectives of this study were to evaluate (i) tissue growth and microvascular development in the equine cyclic luteal structures; (ii) in vitro angiogenic activity of luteal tissues in response to luteotrophic (LH, PGE2) and luteolytic (PGF2) hormones and (iii) to relate data to luteal endocrinological function. Our results show that microvascular density was increased in the early and mid luteal phase, followed by a fall in the late luteal phase and a further decrease in the corpus albicans. Hyperplasia of luteal tissue increased until the mid luteal phase and it was followed by tissue regression. Luteal explants were cultured with no hormone added, or with PGF2, LH, PGE2, LH + PGE2 or LH + PGF2. Media conditioned by equine luteal tissue from different stages of the luteal phase were able to stimulate mitogenesis of bovine aortic endothelial cells (BAEC), suggesting the presence of angiogenic activity. No difference was observed among luteal structures on their mitogenic capacity, for any treatment used. Nevertheless, Late-CL conditioned-media with PGF2 showed a significant decrease in BAEC proliferation (p < 0.05) and LH + PGF2 a tendency to reduce mitogenesis. Thus, prostaglandin F2 may play a role on vascular regression of the CL during the late luteal phase in the mare. These data suggest that luteal angiogenesis and vascular regression in the mare are coordinated with the development of non-vascular tissue and might be regulated by many different factors. 相似文献
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Local regulation of corpus luteum development and regression in the cow: Impact of angiogenic and vasoactive factors 总被引：2，自引：0，他引：2
The corpus luteum (CL) of the estrous cycle in the cow is a dynamic organ which has a life time of approximately 17-18 days. The main function of the CL is to secrete a large amount of progesterone (P) thereby supporting the achievement of pregnancy. As the CL matures, the steroidogenic cells establish contact with many capillaries and the matured CL is composed of many vascular endothelial cells that account for up to 50% of all CL cells. The bovine CL produces several major angiogenic and vasoactive foctors such as vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), angiopoietin-1 and -2 (ANPT-1 and -2), prostaglandin F2α (PGF2α), endothelin-1 (EDN1), angiotensin II (Ang II) and nitric oxide (NO). These factors regulate P secretion directly and/or indirectly within the CL. Moreover, different actions of PGF2α in the early cycle CL (non-luteolytic) and the mid cycle CL (luteolytic) may provide insight into the luteolysis cascade in the cow. The aim of the present review is to describe the current concepts of the local mechanisms for the cascade of development and regression of the bovine CL as regulated by luteal angiogenic and vasoactive factors. 相似文献
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Shirasuna K Nitta A Sineenard J Shimizu T Bollwein H Miyamoto A 《Domestic animal endocrinology》2012,43(2):198-211
The bovine corpus luteum (CL) is a unique, transient organ with well-coordinated mechanisms by which its development, maintenance, and regression are effectively controlled. Angiogenic factors, such as vascular endothelial growth factor A and basic fibroblast growth factor, play an essential role in promoting progesterone secretion, cell proliferation, and angiogenesis. These processes are critically regulated, through both angiogenic and immune systems, by the specific immune cells, including macrophages, eosinophils, and neutrophils, that are recruited into the developing CL. The bovine luteolytic cascade appears to be similar to that of general acute inflammation in terms of time-dependent infiltration by immune cells (neutrophils, macrophages, and T lymphocytes) and drastic changes in vascular tonus and blood flow, which are regulated by luteal nitric oxide and the vasoconstrictive factors endothelin-1 and angiotensin II. Over the period of maternal recognition of pregnancy, the maternal immune system should be well controlled to accept the semiallograft fetus. The information on the presence of the developing embryo in the genital tract is suggested to be transmitted to the ovary by both the endocrine system and the circulating immune cells. In the bovine CL, the lymphatic system, but not the blood vascular system, is reconstituted during early pregnancy, and interferon tau from the embryo could trigger this novel phenomenon. Collectively, the angiogenic and vasoactive factors produced by luteal cells and the time-dependently recruited immune cells within the CL and their interactions appear to play critical roles in regulating luteal functions throughout the life span of the CL. 相似文献
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Maria Florencia Gallelli Carolina Bianchi Enzo Zampini Virginia Trasorras Mariana Gambarotta Marcelo Miragaya 《Reproduction in domestic animals》2020,55(1):74-80
The aim of this study was to characterize corpus luteum vascularization and its association with plasma progesterone concentration in early stages of pregnancy, when maternal recognition of pregnancy is expected to occur. In all animals, both plasma progesterone concentration and corpus luteum vascularization increased from Day 6 to Day 8 post-mating and afterwards in non-pregnant llamas they started to decrease to reach basal levels around Days 12 to 14 post-mating, while in pregnant animals, both variables remained elevated until the end of the study. A lineal positive relationship between corpus luteum vascularization and plasma progesterone concentration was observed in pregnant (r2 = .46, p < .0001) and non-pregnant llamas (r2 = .66, p < .0001). Pregnant animals showed higher plasma progesterone concentration and corpus luteum vascularization than the non-pregnant ones from Day 12 post-mating until the end of the study (p ˂ .05 and p ˂ .01, respectively). These results suggest that maternal recognition of pregnancy should occur before Day 12 post-mating in order to expand luteal lifespan, maintaining corpus luteum vascularization and progesterone production. Also, the assessment of CL vascularization area could be a useful and non-invasive method for early pregnancy diagnosis due to its association with plasma progesterone concentration. 相似文献