交感神经对妊娠早期大鼠子宫内DKK-1和Wnt-1表达的影响

为研究交感神经对妊娠早期子宫内DKK-1和Wnt-1的调控作用,选取180~200日龄健康的性成熟Wistar雌性大鼠,随机分为对照组和处理组,处理组采用静脉注射6-OHDA损毁交感神经,用免疫组化法和qRT-PCR法,观察和分析交感神经对妊娠早期大鼠子宫内膜的DKK-1和Wnt-1蛋白及mRNA相对表达量的影响。结果显示:6-OHDA损毁交感神经后,对卵巢排卵数无显著性影响,但子宫囊胚数量显著下降、囊胚发育延迟,导致子宫腔上皮和腺上皮细胞自分泌DKK-1和Wnt-1紊乱,呈现与正常状态相反的变化趋势。结果表明:在着床窗口期,交感神经通过影响DKK-1对Wnt-1信号分子的调控作用而影响囊胚着床、发育。     

交感神经对妊娠早期大鼠子宫内PCNA表达的影响

为研究妊娠早期子宫内交感神经对PCNA的调控效应,选取180~200日龄健康的性成熟Wistar雌性大鼠36只,随机分为对照组和处理组,处理组采用静脉注射6-OHDA损毁交感神经。采用免疫组化法和qRT-PCR法,观察和分析交感神经对妊娠早期大鼠子宫内膜组织学结构以及PCNA分布的影响。结果表明,PCNA阳性物质主要分布在固有层浅层的蜕膜细胞及肌层的外纵肌细胞核内存在。损毁交感神经后,子宫腺较正常的妊娠状态减少,腺上皮变薄,PCNA免疫阳性细胞减少,子宫内膜的蜕膜细胞及平滑肌细胞等的PCNA发生异常表达,特别是着床前的妊娠第4天(处理组)大鼠子宫腺数量减少,但腺上皮内PCNA免疫阳性细胞增强,子宫正常的组织学微环境被打乱,导致囊胚不能与子宫建立联系,出现着床数下降而排卵数基本正常的状况。免疫组化观察和mRNA相对表达量的统计分析均显示损毁支配子宫的交感神经后,导致子宫组织的蜕膜细胞及平滑肌细胞等的PCNA发生异常表达,打破了正常生理状态下子宫内膜发育与胚泡发育的同步性,影响妊娠早期的胚泡着床。     

交感神经对小鼠妊娠早期血清中性激素的影响

本文运用交感神经阻断剂6-OHDA(100 mg/kg体重)腹腔注射昆明系小鼠,研究交感神经对妊娠早期外周血清性激素水平的影响.结果显示:交感神经损毁后,妊娠早期外周血清中雌二醇浓度着床前(E3)升高明显,着床期下降;血清中孕酮浓度着床前升高,着床后降低.结论:交感神经通过调控妊娠早期外周血性激素的生理水平,从而维持妊娠的发生,促进妊娠早期胚胎发育.     

交感神经阻断小鼠妊娠早期子宫内肥大细胞的分布

为了研究交感神经对哺乳动物早期胚胎发育的影响机制,通过腹腔注射6-羟多巴胺使交感神经阻断后,观察了小鼠妊娠前期胚胎早期发育和肥大细胞数量和型别的变化。结果显示,交感神经阻断后,不仅对胚胎早期发育有影响,使胚胎着床数降低64.4%,而且影响子宫内肥大细胞的数量及其型别分布。妊娠4d(E4)时肥大细胞数量明显升高(P<0.01),同时肥大细胞分型也有所变化,即黏膜型肥大细胞主要存在于胚胎着床前和着床后,结缔组织型肥大细胞没有明显差异,混合型肥大细胞主要存在于着床期间。这一结果表明,妊娠早期子宫肥大细胞数量与型别的变化可能是交感神经影响早期胚胎发育的途径之一。     

牦牛乏情期卵泡发育与17β-雌二醇含量相关分析

选择乏情期牦牛30头,进行卵巢卵泡发育与血浆17β-雌二醇含量相关的分析。结果表明:当卵泡大小在1.0~5.9mm(替补卵泡)时,左右两侧卵巢卵泡数与血浆17β-雌二醇含量呈负相关(P>0.05);当卵泡大小在6.0~8.9mm(选择卵泡)时,左侧卵泡数与血浆17β-雌二醇含量呈显著正相关(P<0.05),而右侧卵巢卵泡数与血浆17β-雌二醇含量呈极显著的正相关(P<0.01);当卵泡大小在9.0~15.0mm(优势卵泡)时,左右两侧卵巢泡数与血浆17β-雌二醇含量呈显著正相关(P<0.05)。     

交感神经对小鼠排卵和早期胚胎发育的影响

为了研究交感神经对妊娠的调控作用,给小鼠连续5 d腹腔注射交感神经化学损毁剂——6-OHDA(100 mg/kg),将交感神经化学性损毁,然后通过阴道涂片法和显微解剖的方法,对交感神经损毁后小鼠发情周期的变化、排卵的数量和妊娠发生后胚胎数量及大小进行了观察。结果表明:交感神经化学损毁后发情周期和排卵的数量没有明显的变化,但是胚胎的数量明显减少,小鼠胚胎数量在妊娠第7天比对照组同期减少了64.4%,在妊娠第9天比对照组同期减少了69.9%;对胚胎的大小进行测量时发现,交感神经损毁组在妊娠第7天与对照组同期相比,长径减小了0.51 mm,短径减小了0.56 mm;妊娠第9天时,交感神经损毁组与对照组同期相比,长径减小了0.37 mm,短径减小了0.47 mm,差异显著(P<0.05)。说明交感神经主要影响胚胎的早期发育,对发情周期和排卵没有明显的影响。     

L-苯丙氨酸对小鼠妊娠早期胚胎发育及子宫局部肥大细胞的影响

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.     

不同剂量6-羟多巴胺对大鼠子宫交感神经损毁情况及其对肥大细胞分布的影响

为研究6-羟多巴胺(6-OHDA)损毁大鼠子宫交感神经的剂量及其对子宫肥大细胞分布的影响,选取180~200日龄健康的性成熟Wistar雌性大鼠24只,随机分为对照组和处理组,处理组尾静脉注射25,50,100 mg/kg的6-OHDA。结果显示:按照一次性注射100mg/kg 6-OHDA的方法可以损毁支配子宫的交感神经,而50 mg/kg未能损毁子宫内膜固有层的神经。肥大细胞观察结果显示,其主要分布在内环、外纵肌之间的血管周围,随着6-OHDA剂量的不断加大,肥大细胞数量呈减少趋势,3个处理组对比差别显著,对照组略高于25 mg/kg组。血清中组织胺含量呈相反的变化趋势。结果表明,可采取一次性注射100mg/kg的6-OHDA来建立交感神经损毁模型,交感神经影响子宫内肥大细胞的分布,对于机体组织胺释放的调控不同于子宫。     

粟糠对母猪妊娠前期行为、血液生化指标及生殖激素的影响

粟糠中含有丰富的纤维素和半纤维素,是一种产量较大的可再生利用资源,是重要的膳食纤维来源,但是粟糠在母猪上的应用报道很少。为研究粟糠对妊娠母猪前期的行为、血清生化指标及生殖激素的影响,试验选用32头胎次、配种时间及体况均相近的"大×长"二元母猪,采用单因子完全随机设计,分对照组、试验Ⅰ组、试验Ⅱ组和试验Ⅲ组,每组8个重复,限位栏饲养,粟糠的添加水平分别为:0%、9%、17%和24.5%,每组的消化能和粗蛋白质基本一致。结果表明:(1)日粮添加粟糠降低了妊娠母猪前期咬栏行为(P<0.05)、舔地行为和站立时间(P<0.01),增加趴卧时间(P<0.05)。(2)降低血清总胆固醇含量(P<0.01)、雌二醇含量(P<0.05),增加孕激素含量(P<0.01)。本试验研究表明妊娠母猪前期日粮中添加粟糠增加了母猪的趴卧休息时间,降低了咬栏、添地等刻板行为,降低血清总胆固醇含量和雌二醇含量,提高了孕激素含量,有利用母猪孕期的子宫内膜增生,受精卵植入,并降低子宫肌肉兴奋度,保证孕期安全。     

共轭亚油酸对小鼠产子数及血清中4种生殖相关指标的影响

试验旨在研究共轭亚油酸(CLA)对小鼠生殖性能的影响。试验选用60只6~7周龄的昆明雌性小鼠,随机分为2组。对照组饲喂添加1.5%花生油的繁殖颗粒料,试验组饲喂添加1.5%花生油和1.5%共轭亚油酸的繁殖颗粒料。采用酶联免疫法测定间情期、发情期、妊娠5 d和妊娠9 d小鼠的血清瘦素、内脂素、雌二醇(E2)和孕酮(P)含量,并计胚胎数(妊娠5 d和9 d)及产子数,每组各6只。结果表明:共轭亚油酸可显著降低各阶段的血清瘦素、内脂素和雌二醇水平(P0.01或P0.05);可使血清孕酮水平升高,并在间情期、妊娠5 d和妊娠9 d时差异极显著(P0.01);显著增加窝产子数(P0.05)。综上所述,共轭亚油酸能够影响血清瘦素、雌激素和孕酮水平,提高小鼠的生殖能力。     

Production of calcium maintenance factor Stanniocalcin-1 (STC1) by the equine endometrium during the early pregnant period

A factor responsible for progression to pregnancy establishment in the mare has not been definitively characterized. To identify factors possibly involved in the establishment of equine pregnancy, the endometrium was collected from day 13 (day 0=day of ovulation) cyclic and day 13, 19 and 25 pregnant animals. From initial subtractive hybridization studies, a calcium regulating factor, Stanniocalcin-1 (STC1) mRNA, was found as a candidate molecule expressed uniquely in the pregnant endometrium. Endometrial expression of STC1 mRNA was noted on day 19 and was markedly increased in the day 25 gravid endometrium. STC1 protein was found in the extracts of day 25 gravid endometrium and immunochemically localized in the uterine glands. In addition, STC1 protein was detected in uterine flushing media collected from day 25 pregnant mares. High concentrations of estradiol-17 β (E(2)) were detected in day 25 conceptuses. E(2) levels were much higher in the gravid endometrium than in other regions, whereas progesterone levels did not differ among the samples from different endometrial regions. Expression of STC1 mRNA, however, was not significantly upregulated in cultured endometrial explants treated with various concentrations of E(2) (0.01-100 ng/ml) with or without 10 ng/ml progesterone. These results indicate that an increase in STC1 expression appears to coincide with capsule disappearance in the conceptus, and suggest that STC1 from the uterine glands likely plays a role in conceptus development during the pregnancy establishment period in the mare.     

大肠杆菌与金黄色葡萄球菌对奶牛子宫内膜组织细胞因子表达及损伤程度的影响

本试验旨在研究体外感染金黄色葡萄球菌与大肠杆菌对奶牛子宫内膜组织中细胞因子白介素-6（IL-6）、IL-1β和IL-8的表达及损伤程度的影响。以体外培养的奶牛子宫内膜组织作为研究对象,采用1×10⁵~1×10⁹ CFU/mL大肠杆菌与金黄色葡萄球菌对奶牛子宫内膜组织进行体外感染,通过实时荧光定量PCR和ELISA方法检测两种细菌刺激后奶牛子宫内膜组织中IL-6、IL-1β及IL-8 mRNA与蛋白的表达量,并用HE染色法观察两种细菌感染后奶牛子宫内膜组织病理学切片。结果显示,1×10⁵~1×10⁹ CFU/mL大肠杆菌体外感染后,奶牛子宫内膜组织中IL-6、IL-1β和IL-8 mRNA表达量均极显著高于空白对照组（P<0.01）;金黄色葡萄球菌感染浓度为1×10⁵、1×10⁶ CFU/mL时,IL-6、IL-1β mRNA表达量极显著高于空白对照组（P<0.01）,感染浓度为1×10⁷ CFU/mL时,IL-6、IL-1β mRNA表达量显著高于空白对照组（P<0.05）,感染浓度为1×10⁶ CFU/mL时,IL-8 mRNA表达量显著高于空白对照组（P<0.05）,其他感染浓度均与空白对照组无显著差异（P>0.05）。奶牛子宫内膜组织感染1×10⁵~1×10⁹ CFU/mL金黄色葡萄球菌和大肠杆菌时,IL-6、IL-1β及IL-8蛋白表达量均极显著高于空白对照组（P<0.01）。相同浓度的大肠杆菌感染奶牛子宫内膜组织后,IL-6、IL-1β及IL-8 mRNA与蛋白表达量均极显著高于金黄色葡萄球菌感染组（P<0.01）。HE切片染色结果显示,大肠杆菌感染后仍有部分上皮细胞保留,而金黄色葡萄球菌感染后上皮细胞全部脱落。本试验结果表明,大肠杆菌与金黄色葡萄球菌感染奶牛子宫内膜组织后,引起的炎症反应不同。大肠杆菌感染后,促炎性细胞因子被显著上调,而金黄色葡萄球菌感染后破坏子宫内膜上皮细胞程度更加严重。     

The Effect of Manual Removal of Placenta Immediately after Foaling on Subsequent Fertility Parameters in the Mare

Retained placenta is considered to be a common problem in postpartum mares. The incidence varies from 6% to 54% depending on the breed, with higher incidence in heavy draught mares than in light-weight mares. Retained placenta has been linked to lower postpartum oxytocin concentration, impaired uterine involution, and dystocia. The objective of this study was to assess the effect of early manual removal of placenta immediately postpartum on subsequent fertility parameters (development of free intrauterine fluid, inflammatory status of endometrium, and on pregnancy rates) and to compare them with mares with spontaneous expulsion of placenta. A total of 29 mares, mainly Irish draught, were closely monitored during foaling by closed circuit television and allocated to two groups: (1) mares that expelled the placenta spontaneously within 3 hours of foaling; and (2) mares that were cleansed manually immediately after foal delivery. All mares were examined and scanned 5 and 9 days postpartum, and free intrauterine fluid was recorded; endometrial swabs were taken 9 days postpartum for endometrial cytology and culture. None of the fertility parameters analyzed showed statistical difference between groups 1 and 2. Therefore, it can be concluded that early manual removal of placenta has no detrimental effects on subsequent fertility of mares and, therefore, can be recommended when a veterinarian attends a foaling.     

Identification of elevated concentrations of estradiol in bovine uterine endometrium

We have investigated the estradiol content of bovine endometrium and related this to circulating plasma estradiol content. In 9 heifers, mean ± S.E.M. plasma estradiol concentration was 0.64 ± 0.25 pg/ml while the mean ± S.E.M. endometrial estradiol content was 43.0 ± 14.7 pg/g tissue; there was a close relationship between plasma and tissue estradiol levels (R² = 0.81; P < 0.001). During culture of endometrial tissue there was a progressive transfer of estradiol from tissue to culture media but no change in total estradiol. Culture of endometrium from 4 heifers with 5 ng/ml testosterone for 72 h resulted in no increase in estradiol. Furthermore, immunohistochemistry revealed no aromatase protein in uterine endometrium. These results confirm high stored tissue concentrations of estradiol in bovine endometrium while providing no evidence for estradiol synthesis by this tissue. The mechanism(s) through which this sequestration of estradiol into uterine tissue occurs remains to be determined.     

The oestrous cycle and early pregnancy--a new concept of local endocrine regulation

Facts discovered in recent decades have compelled us to revise long-established views on the physiological regulation of cyclic adjustments to the reproductive system in preparation for pregnancy in females. Evidence has been presented to show that changes in the uterine blood supply induced by the oestrogen/progesterone ratio in the blood and cytokines are important in the regulation of the secretory function of the endometrium. Progressive reduction in uterine blood flow during the luteal phase of the oestrous cycle causes regressive changes in endometrial cells and release of prostaglandin (PG) F(2 alpha), resulting in initiation of luteolysis. Retrograde transfer of PGF(2 alpha) in the area of the mesometrium vasculature is an important element in the mechanism protecting the corpora lutea against luteolysis before day 12 of the porcine oestrous cycle and during early pregnancy and pseudopregnancy. Results of many studies presented in this review indicate that PGF(2 alpha) pulses in uterine venous blood during the follicular phase of the oestrous cycle may not be due to PGF(2 alpha) secretion by endometrial cells, but occur due to remodeling of the endometrium and pulsatile exretion of PGF(2 alpha) in accordance with rhythmic uterine contractions caused by oxytocin.     

Modulation of the effects of norepinephrine uptake inhibitors on the norepinephrine-induced contractile response of the porcine uterine artery during early pregnancy.

The effects of norepinephrine (NE) uptake inhibitors on the porcine uterine artery's contractile response to NE and their potential alteration during early pregnancy (Day 13 postcoitus; day of coitus = Day 0) in comparison with the end of the luteal phase (Days 11-14; first day of behavioral estrus = Day 0) was investigated. This pregnancy time point is characterized by a transient increase in resting uterine blood flow dependent on the presence of blastocysts, an increased endometrial vascular permeability, and the beginning of the endometrial attachment of the blastocysts. A cumulative concentration-response curve (CCRC) to NE was produced in isometrically-mounted rings. Cocaine (5 microM) was used to inhibit neuronal NE uptake and hydrocortisone (30 microM) was used to inhibit extraneuronal NE uptake. Either drug alone induced a leftward shift of the CCRC to NE without affecting the maximal response. This shift had the same amplitude at the end of the luteal phase and in early pregnancy. However, the leftward shift induced by cocaine was larger than that induced by hydrocortisone only in early pregnancy, and the leftward shift induced by exposure to both hydrocortisone and cocaine was larger in early pregnancy than at the end of the luteal phase. These results suggest that a significant sensitization of the contractile response of the porcine uterine artery to NE is induced by neuronal and extraneuronal uptake inhibitors and that this effect is altered in early pregnancy, possibly reflecting the existence of a mechanism protecting the uterine artery against excessive sympathetic stimulation.