胎儿生长受限模型及其胎盘的病理学观察

目的证实胎儿生长受限大鼠模型的建立方法;观察胎儿生长受限(FGR)大鼠胎盘的组织形态及超微结构特征。方法健康Wistar雌鼠24只,按妊娠先后顺序随机分为两组:正常对照组(正常组)、模型组(烟酒处理组),采用烟酒混合因素建立大鼠FGR模型;比较两组胎鼠的体重、鼻臀长度、体重系数及FGR发生率,两组胎盘组织行HE染色,并应用光镜和电镜观察其病理变化。结果①模型组胎仔平均体重、鼻臀长度、体重系数较正常组分别减轻46.0%、21.9%、35.0%(P0.01)。对照组FGR发生率仅为12.5%,模型组FGR发生率为79.3%,显著高于对照组(P0.01)。②模型组胎盘形态学明显改变。结论通过烟酒干预的方法,成功建立缺血缺氧性FGR孕鼠模型。烟酒可导致胎盘形态结构的改变,这种病理改变是造成FGR胎盘功能减退的形态学基础。     

SD大鼠胚胎-胎仔发育毒性试验的基础数据

目的 检测胚胎-胎仔发育毒性试验中SD大鼠妊娠期的体重、生殖功能指标及胎鼠的各项发育指标,为SD大鼠的发育毒性研究提供参考数据.方法 395只SD雌性大鼠,交配成功后,于妊娠第20天剖检孕鼠,检查孕鼠的内脏器官有无异常,称量子宫重量、窝重和胎盘重量,计数黄体数、着床数、活胎数、吸收胎数和死胎数.胎鼠共5272只,将一半胎鼠放人固定液中做内脏检查,另一半胎鼠进行骨骼检查,检查胎鼠外观、内脏和骨骼有无异常和变异.结果 和结论 建立SD大鼠胚胎-胎仔发育毒性试验中各项指标的数据库,求得各指标的正常值及标准差,95％的可信区间,为生殖毒性研究提供正常值的参考依据.     

川芎嗪合并硫酸镁治疗妊高征大鼠的疗效及机制探讨

为探讨川芎嗪合并硫酸镁治疗妊高征模型大鼠的疗效及其机制,应用L-NAME7mg/kg/天尾静脉注射,连续4天,建立大鼠妊高征模型,采用川芎嗪合并硫酸镁(川 硫)治疗,连续3天。通过套尾法血压测量和24h尿蛋白测定,观察妊高征孕鼠分组治疗后的各组孕鼠血压、尿蛋白变化。并作新生鼠身长、体重和胎盘重量测定,光镜和透射电镜观察肝、肾和胎盘组织病理学及超微结构变化。结果显示,妊娠晚期给予L-NAME,可导致孕鼠血压升高,尿蛋白增加,幼鼠死胎及畸形发生率增加;单用硫酸镁、川芎嗪或两药合用后孕鼠血压、尿蛋白均显著降低(p<0.01,p<0.001),而(川 硫)组较另两组降低更显著(p<0.01,p<0.001);川芎嗪及(川 硫)治疗后能增加新生鼠身长、提高胎仔体重及胎盘重量(p<0.01);且后者尚能减少胎仔后肢短缩畸形率(p<0.001)。妊高征孕鼠肝细胞有散在的坏死灶;肾小球基底膜广泛增厚、肾小球血管内皮肿胀,肾小管上皮广泛水肿;胎盘蜕膜带、基带均增厚,滋养细胞表面的微绒毛减少;川芎嗪尤其(川 硫)治疗后肝细胞未见坏死灶,肾小球基底膜增厚减少;而且后者肾小球血管内皮形态基本正常,肾小管上皮细胞胞浆水肿减轻;胎盘病变明显减轻。上述结果表明,(川 硫)治疗妊高征孕鼠,效果优于单用硫酸镁或川芎嗪。妊高征孕鼠胎盘存在缺血、缺氧的病理改变;川芎嗪治疗组尤其(川 硫)治疗后肝、肾和胎盘病变明显减轻。     

新生小鼠急性脑缺氧缺血动物模型的建立

目的建立急性脑缺氧缺血的动物模型.方法采用足月妊娠小鼠(查到阴道栓后19.5d),用剖宫手术方法,暴露子宫,用止血钳阻断双侧子宫动脉血管,致使缺氧缺血后脑部发生病理改变.结果随着阻断子宫血管时间的延长,胎鼠的死亡率增高,两者具有直线正相关关系(P＜0.05).实验组胎鼠体重(出生至离乳)增长缓慢,胎鼠爬、翻身及对应激刺激等的运动发育明显迟缓,脑部的病理改变明显,与人的急性脑缺氧缺血的临床表现,脑部病理变化及其后遗症是相似的.结论采用小鼠做急性脑缺氧缺血的动物模型,脑缺氧缺血效果明显,本模型的建立,可用于人的急性脑缺氧缺血的病理学、生理学及其药物治疗等诸多方面的类比实验研究.     

VEGF异常与胎儿生长受限

VEGF正常表达是妊娠正常进行的关键环节,其对胎盘血管形成、胎盘绒毛细胞和子宫螺旋动脉的发生发展起着至关重要的作用。VEGF异常导致子宫、胎盘血管发育障碍,胎儿缺血缺氧,最终导致胎儿生长受限。本文主要从VEGF对胎盘血管生成、胎盘绒毛膜炎、绒毛细胞凋亡、子宫螺旋动脉重塑异常及生殖微生物等方面的影响进行简要综述,为今后临床通过VEGF早期预测胎儿生长受限并评估其治疗及预后提供理论依据。     

改良法建立妊娠期高血压疾病大鼠模型

目的寻找理想的妊娠期高血压疾病动物模型。方法60只雌性Wistar大鼠分为六组,分别为正常妊娠组（A组）、左旋亚硝酸精氨酸甲酯（L-NAME）腹腔注射组（B组）、生理盐水注射组（C组）、假手术组（D组）、双侧子宫动脉结扎术组（E组）以及L-NAME腹腔注射联合腹主动脉缩窄术组（F组）,对大鼠血压、尿蛋白值以及胎鼠、胎盘、胎鼠头的重量进行监测并观察肾脏、胎盘的病理改变。结果F组孕鼠于孕13d即出现了蛋白尿、血压升高,较B组及E组出现时间早（P〈0.05）,其胎鼠体重、胎头重量下降较各组更明显（P〈0.05）,肾小球小动脉管壁增厚、管腔狭窄;胎盘出现血管间膜增厚、纤维蛋白沉积等妊娠高血压疾病的典型病理改变。结论L-NAME腹腔注射联合腹主动脉缩窄术是更为理想的建立妊娠高血压疾病动物模型的方法。     

寒冷刺激对孕鼠子代生长发育的影响

目的：探讨寒冷刺激对孕鼠子代生长发育的影响。方法：将孕鼠分为正常妊娠组和冷激妊娠组,正常妊娠组25℃饲养,冷激妊娠组每日8：00—12：00置于（4±2）℃环境下寒冷刺激。18d后测量孕鼠血压,剖宫记录胎鼠、胎盘、羊水重量,测量初生仔鼠、内脏器官重及内脏器官与体重比值,绘制1—44d的生长曲线、每日增重率曲线,测量出生8周后子代的血压。结果：冷激妊娠组孕鼠血压高于正常妊娠组（P〈0．05）,胎鼠、胎盘、羊水重量显著低于正常妊娠组（P〈0．01）,冷激妊娠组仔鼠内脏器官重显著低于正常妊娠组（P〈0．05）,两组内脏器官与体重比值比较无统计学意义（P〉0．05）。1～44d的生长曲线表明直到性成熟冷激妊娠组子代的体重仍没有追上正常妊娠组,但两组每日增重率曲线基本吻合。冷激妊娠组子代的血压显著高于正常妊娠组（P〈0．05）。结论：寒冷刺激严重影响子代的生长和发育。     

三聚氰胺对SD孕鼠及胎鼠的毒作用

为阐明三聚氰胺对孕鼠和胎鼠毒性作用,将40只SD孕鼠随机分为高剂量组(Ⅰ)、中剂量组(Ⅱ)、低剂量组(Ⅲ)及空白对照组(Ⅳ),共4组,于妊娠第6~19天,分别经口灌服800 mg/kg·d、200 mg/kg·d、20 mg/kg·d和0 mg/kg·d三聚氰胺混悬液。染毒期间,观察孕鼠中毒表现,以及不同妊娠时间体重变化;于妊娠第20天处死母鼠,检测血清尿素氮、肌酐及尿酸,胎鼠及胎盘重量等指标;观察母鼠和胎儿肾脏、胎盘组织病理变化。结果显示,在染毒期,Ⅰ、Ⅱ组母鼠出现精神差等症状;与Ⅳ组相比,Ⅰ、Ⅱ组母鼠、胎鼠和胎盘重量,血液生化指标有显著或极显著差异(P0.05或P0.01),且Ⅰ、Ⅱ组母鼠、胎鼠肾脏以及胎盘有明显病理变化;但3个剂量水平的三聚氰胺对胚胎的存活无影响,也不产生致畸作用。     

产前超声孕妇血流动力学血流参数监测对中晚期胎儿宫内生长受限临床意义分析

摘要 目的：通过监测产前彩色多普勒超声心动图子宫动脉、脐动脉和大脑中动脉的血流参数,进而分析其在中晚期宫内胎儿生长受限（FGR）的临床意义。方法：以我院2020年1月-2021年12月就诊的中晚期孕妇为研究对象,其中110例为孕晚期FGR孕妇,60例为孕晚期健康孕妇,分别记录为FGR组（n=110）和对照组（n=60）,用彩色多普勒超声监测两组孕晚期孕妇的多血管（子宫动脉、脐动脉和大脑中动脉）的3个血流参数,对比两组之间血流参数的差异性;并根据Apgar评分,比较不同Apgar评分下的血流参数差异,分析子宫动脉、脐动脉和大脑中动脉的3个血流参数与宫内FGR的相关性。结果：（1）FGR组胎儿子宫动脉的3个血流参数（RI、PI、S/D）均显著高于对照组（P<0.05）;（2）FGR组胎儿脐动脉的3个血流参数（RI、PI、S/D）均显著高于对照组（P<0.05）;（3）FGR组胎儿大脑中动脉的3个血流参数（RI、PI、S/D）均显著低于对照组（P<0.05）;（4）Apgar≤7分组子宫动脉的3个血流参数（RI、PI、S/D）显著高于Apgar＞7分组,Apgar≤7分组脐动脉的3个血流参数（RI、PI、S/D）显著高于Apgar＞7分组,Apgar≤7分组大脑中动脉的3个血流参数（RI、PI、S/D）显著低于Apgar＞7分组。结论：彩色多普勒超声心动图子宫动脉、脐动脉、大脑中动脉3个血流参数（RI、PI、S/D）异常与FGR的发生密切相关,为临床筛查和诊断FGR提供有用帮助。     

丹参治疗胎儿生长受限的疗效分析

目的探讨丹参对胎儿生长受限(FGR)的疗效。方法选择我院及廊坊卫生职业学院2012年1月~2014年1月收治的产前检查诊断为FGR者71例,随机分成二组:实验组35例,对照组36例。对照组用能量合剂+复方氨基酸等药物静滴;实验组在对照组的基础上加用丹参注射液16ml静滴。结果实验组在胎儿双顶径(BPD)增长,脐动脉S/D比值下降较对照组疗效明显,差异有统计学意义(P0.05)。结论丹参能有效改善子宫胎盘的血流灌注,促进胎儿生长,对治疗FGR有效。     

Transplacental penetration of 7,12-dimethylbenz(a)anthracene and its distribution in the organs of rat fetuses]

Rats were given 7,12-dimethylbenz(a)anthracene (DMBA) intravenously in a dose of 15 mg/kg on the 21st day of pregnancy; its content in the liver, placenta, and the fetus was determined by the fluorescent-spectral method. The maximal concentration was reached in 10--15 min in the liver and placenta of the pregnant rats (45 and 6.3 microgram/kg, respectively) in comparison with a slower (in one hour) elevation in the fetal tissues (2.4 microgram/kg). It took about 5 hours for all the tissues to be cleared of the carcinogen. One hour after the administration DMBA was unevenly distributed in various fetal organs--the maximal content in the liver, and the minimal--in the "carcass" in comparison with the content in other organs (the kidneys, lungs, brain, intestine). The results obtained failed to correlate with the data on the predominant origination of the tumours in the kidneys and the nervous system of rats in transplacental DMBA action.     

Sildenafil Citrate Increases Fetal Weight in a Mouse Model of Fetal Growth Restriction with a Normal Vascular Phenotype

Fetal growth restriction (FGR) is defined as the inability of a fetus to achieve its genetic growth potential and is associated with a significantly increased risk of morbidity and mortality. Clinically, FGR is diagnosed as a fetus falling below the 5^th centile of customised growth charts. Sildenafil citrate (SC, Viagra™), a potent and selective phosphodiesterase-5 inhibitor, corrects ex vivo placental vascular dysfunction in FGR, demonstrating potential as a therapy for this condition. However, many FGR cases present without an abnormal vascular phenotype, as assessed by Doppler measures of uterine/umbilical artery blood flow velocity. Thus, we hypothesized that SC would not increase fetal growth in a mouse model of FGR, the placental-specific Igf2 knockout mouse, which has altered placental exchange capacity but normal placental blood flow. Fetal weights were increased (by 8%) in P0 mice following maternal SC treatment (0.4 mg/ml) via drinking water. There was also a trend towards increased placental weight in treated P0 mice (P = 0.056). Additionally, 75% of the P0 fetal weights were below the 5^th centile, the criterion used to define human FGR, of the non-treated WT fetal weights; this was reduced to 51% when dams were treated with SC. Umbilical artery and vein blood flow velocity measures confirmed the lack of an abnormal vascular phenotype in the P0 mouse; and were unaffected by SC treatment. ¹⁴C-methylaminoisobutyric acid transfer (measured to assess effects on placental nutrient transporter activity) per g placenta was unaffected by SC, versus untreated, though total transfer was increased, commensurate with the trend towards larger placentas in this group. These data suggest that SC may improve fetal growth even in the absence of an abnormal placental blood flow, potentially affording use in multiple sub-populations of individuals presenting with FGR.     

eNOS knockout mouse as a model of fetal growth restriction with an impaired uterine artery function and placental transport phenotype

Fetal growth restriction (FGR) is the inability of a fetus to reach its genetically predetermined growth potential. In the absence of a genetic anomaly or maternal undernutrition, FGR is attributable to "placental insufficiency": inappropriate maternal/fetal blood flow, reduced nutrient transport or morphological abnormalities of the placenta (e.g., altered barrier thickness). It is not known whether these diverse factors act singly, or in combination, having additive effects that may lead to greater FGR severity. We suggest that multiplicity of such dysfunction might underlie the diverse FGR phenotypes seen in humans. Pregnant endothelial nitric oxide synthase knockout (eNOS(-/-)) dams exhibit dysregulated vascular adaptations to pregnancy, and eNOS(-/-) fetuses of such dams display FGR. We investigated the hypothesis that both altered vascular function and placental nutrient transport contribute to the FGR phenotype. eNOS(-/-) dams were hypertensive prior to and during pregnancy and at embryonic day (E) 18.5 were proteinuric. Isolated uterine artery constriction was significantly increased, and endothelium-dependent relaxation significantly reduced, compared with wild-type (WT) mice. eNOS(-/-) fetal weight and abdominal circumference were significantly reduced compared with WT. Unidirectional maternofetal (14)C-methylaminoisobutyric acid (MeAIB) clearance and sodium-dependent (14)C-MeAIB uptake into mouse placental vesicles were both significantly lower in eNOS(-/-) fetuses, indicating diminished placental nutrient transport. eNOS(-/-) mouse placentas demonstrated increased hypoxia at E17.5, with elevated superoxide compared with WT. We propose that aberrant uterine artery reactivity in eNOS(-/-) mice promotes placental hypoxia with free radical formation, reducing placental nutrient transport capacity and fetal growth. We further postulate that this mouse model demonstrates "uteroplacental hypoxia," providing a new framework for understanding the etiology of FGR in human pregnancy.     

Influence of dexamethasone on growth and development of rat fetuses: changes in nucleic acids and protein content

Pregnant rats were treated with dexamethasone in drinking water (10 micrograms/ml) from the 15th to the 22nd day of pregnancy. Dexamethasone significantly reduced the weight of rat fetuses and concentration of DNA, RNA and proteins in fetal adrenal glands, liver, placenta, brain, kidneys, heart, lung, testes and pituitary from the 17th to the 22nd day of pregnancy. These data show that dexamethasone given to pregnant rat may lead to potentially deleterious effects on fetal rat development.     

Local increase of ovarian steroid hormone concentration in blood supplying the oviduct and uterus during early pregnancy of sows

Countercurrent transfer in the ovarian vascular pedicle elevates the concentration of steroid hormones in blood supplying the oviduct and periovarian part of the uterus during the estrous cycle in the pig. This study was conducted to determine whether during early pregnancy the arterial blood supply to the oviduct and uterus carries greater concentration of steroid hormone than systemic blood. The concentration of ovarian steroid hormones (progesterone, estradiol-17 beta, estrone, androstenedione and testosterone) was measured in 40 gilts on Days 12, 18, 25 or 35 of pregnancy. Silastic catheters were inserted: a) into the jugular vein, b) into the branch of uterine artery close to the ovary (proximal to the ovary) and c) into the branch of the uterine artery close to the cervix (distal to the ovary). On the day following surgery simultaneous blood samples from cannulated vessels were collected every 20 min for 3 hours. The concentration of steroid hormones was determined by radioimmunoassay. The mean concentrations of studied hormones in branches of the uterine artery proximal and distal to the ovary were significantly greater than in the jugular vein (P < 0.001) by 18 to 69% and 7 to 31%, respectively. The concentrations of hormones in proximal and distal to the ovary branch of the uterine artery were also significantly different (P < 0.001). The increase in concentrations of the measured hormones did not differ considerably between investigated days of pregnancy. It is concluded that during maternal recognition of pregnancy, formation of the corpus luteum of pregnancy, implantation of the embryo and the placenta elongation the oviduct and uterus are supplied with locally elevated concentration of steroid hormones compared to systemic blood.     

ACE2 expression and activity are enhanced during pregnancy

In the current study, we investigated the expression and activity of ACE2 during pregnancy in normotensive and hypertensive rats, focusing on the relative contribution of the uterus and the placentas, the kidney serving as a reference. We used the Sabra rat model of salt-sensitive hypertension. We confirmed a systemic vasodilatory state during the third trimester of pregnancy, as evidenced by a reduction in blood pressure, both in normotensive and hypertensive rats. At the time that blood pressure was reduced, ACE2 was expressed abundantly in the reproductive organs. The relative levels of ACE2 mRNA in the pregnant animal were placenta > kidneys > or = uterus and of ACE2 activity kidney > placenta > uterus. In the uterus and the placenta, ACE2 expression was unaffected by strain, salt-loading, or the level of blood pressure. ACE2 activity in the uterus of the nonpregnant rat was not affected by any of these variables either, but during pregnancy increased in salt-loaded animals. When estimating the total contribution of the uterus to ACE2 mRNA and activity during pregnancy, we found that the amount of ACE2 mRNA increased in both strains irrespective of diet, but that ACE2 activity increased only in salt-loaded animals. We further estimated the relative total contribution of the uterus, placentas, and kidneys to ACE2 expression and activity during pregnancy by adjusting for mass and number of organs and found that the placentas were the major contributors, followed by the kidney and the uterus. We conclude that during pregnancy, the placentas, in particular, but also the uterus, constitute important sources of ACE2, in addition to its normal production in the kidney, leading to an estimated twofold increase in total ACE2 activity. These data are consistent the hypothesis that transient ACE2 overexpression and increased activity during pregnancy may be important in modulating systemic, as well as local hemodynamics in the uteroplacental unit.     

子宫动脉栓塞术后并发血栓的临床病例分析和诊治探讨

目的:探讨剖宫产瘢痕妊娠(CSP)患者经子宫动脉栓塞术(UAE)后并发下肢深静脉血栓(DVT)的临床病例的诊断治疗要点。方法:回顾性分析2014年-2016年我院收治的剖宫产瘢痕妊娠患者经子宫动脉栓塞术后并发下肢深静脉血栓(DVT)5例患者的临床特点及诊断、治疗方法。结果:2014年-2016年,我院CSP患者经UAE治疗后发生DVT的发病率为1.63%,患者平均年龄35.2岁。DVT临床症状出现于UAE术后3-6天,多表现为下肢的疼痛及酸胀,深静脉血栓均出现在介入穿刺处肢体。用彩色多普勒血流显像诊断深静脉血栓安全可靠。采用低分子肝素皮下注射抗凝治疗均取得较好效果。结论:剖宫产瘢痕妊娠患者经子宫动脉栓塞术治疗后有发生下肢深静脉血栓风险,DVT发生与穿刺处肢体制动,血管受压,血液回流障碍有关。手术前后应采取预防措施,低分子肝素钠抗凝对DVT治疗有效。